Is it right to say that global warming is fact?

brianthebard

A while ago minister Gormley stated that the time for debate is over and that global warming is now undeniable fact. (Not a direct quote). However even if the evidence is extremely strong surely it is important that people not start to be jump the gun and pronounce things to be fact that scientifically or actually speaking, aren't yet fact?

fits

www.ipcc.ch

*yawns*

From the Fourth Assessment Report

• Eleven of the last twelve years (1995–2006) rank among the 12 warmest years in the instrumental record of global surface temperature (since 1850). The updated 100-year linear trend (1906 to 2005) of 0.74°C [0.56°C to 0.92°C] is therefore larger than the corresponding trend for 1901 to 2000 given in the Third Assessment Report (TAR) of 0.6°C [0.4°C to 0.8°C]. The warming trend shows an acceleration for the second part of the last century.

• The average atmospheric water vapour content has increased since at least the 1980s over land and ocean as well as in the upper troposphere. The increase is broadly consistent with the extra water vapour that warmer air can hold.

• Observations since 1961 show that the average temperature of the global ocean has increased to depths of at least 3000 m and that the ocean has been absorbing more than 80% of the heat added to the climate system. Such warming causes seawater to expand, contributing to sea level rise.

• Mountain glaciers and snow cover have declined on average in both hemispheres. Widespread decreases in glaciers and ice caps have contributed to sea level rise (ice caps do not include contributions from the Greenland and Antarctic Ice Sheets).

• New data since the TAR now show that losses from the ice sheets of Greenland and Antarctica have very likely contributed to sea level rise over 1993 to 2003. Flow speed has increased for some Greenland and Antarctic outlet glaciers, which drain ice from the interior of the ice sheets. The corresponding increased ice sheet mass loss has often followed thinning, reduction or loss of ice shelves or loss of floating glacier tongues. Such dynamical ice loss is sufficient to explain most of the Antarctic net mass loss and approximately half of the Greenland net mass loss. The remainder of the ice loss from Greenland has occurred because losses due to melting have exceeded accumulation due to snowfall.

• Global average sea level rose at an average rate of 1.8 [1.3 to 2.3] mm per year over 1961 to 2003. The rate was faster over 1993 to 2003: about 3.1 [2.4 to 3.8] mm per year. Whether the faster rate for 1993 to 2003 reflects decadal variability or an increase in the longer term trend is unclear. There is high confidence that the rate of observed sea level rise increased from the 19th to the 20th century. The total 20th-century rise is estimated to be 0.17 [0.12 to 0.22] m.

• Average arctic temperatures increased at almost twice the global average rate in the past 100 years. Arctic temperatures have high decadal variability, and a warm period was also observed from 1925 to 1945.

• Satellite data since 1978 show that annual average arctic sea ice extent has shrunk by 2.7 [2.1 to 3.3]% per decade, with larger decreases in summer of 7.4 [5.0 to 9.8]% per decade. These values are consistent with those reported in the TAR.

• Temperatures at the top of the permafrost layer have generally increased since the 1980s in the Arctic (by up to 3°C). The maximum area covered by seasonally frozen ground has decreased by about 7% in the Northern Hemisphere since 1900, with a decrease in spring of up to 15%.

• Long-term trends from 1900 to 2005 have been observed in precipitation amount over many large regions. Significantly increased precipitation has been observed in eastern parts of North and South America, northern Europe and northern and central Asia. Drying has been observed in the Sahel, the Mediterranean, southern Africa and parts of southern Asia.

• Changes in precipitation and evaporation over the oceans are suggested by freshening of mid- and high-latitude waters together with increased salinity in low-latitude waters.

• Mid-latitude westerly winds have strengthened in both hemispheres since the 1960s.


• More intense and longer droughts have been observed over wider areas since the 1970s, particularly in the tropics and subtropics. Increased drying linked with higher temperatures and decreased precipitation has contributed to changes in drought. Changes in sea surface temperatures, wind patterns and decreased snowpack and snow cover have also been linked to droughts.

• The frequency of heavy precipitation events has increased over most land areas, consistent with warming and observed increases of atmospheric water vapour.

• Widespread changes in extreme temperatures have been observed over the last 50 years. Cold days, cold nights and frost have become less frequent, while hot days, hot nights and heat waves have become more frequent.

• There is observational evidence for an increase in intense tropical cyclone activity in the North Atlantic since about 1970, correlated with increases of tropical sea surface temperatures.

• Antarctic sea ice extent continues to show interannual variability and localised changes but no statistically significant average trends, consistent with the lack of warming reflected in atmospheric temperatures averaged across the region.
For the first time, wide-ranging impacts of changes in current climate have been documented: retreating glaciers, longer growing seasons, shift of species ranges, and health impacts due to a heatwave of unprecedented magnitude. The observed changes described above are consistent with those projected for future climate change.

piraka

fits wrote:

www.ipcc.ch

*yawns*

From the Fourth Assessment Report

How much of what you have quoted is due to natural processes and how much is due to increased CO2 in the troposphere?

dudara

Personally, I would not say something is fact (how do we know with absolute certainty? Theories are developed every day, it takes the test of time and the support of evidence for them to endure), but I will say that there is a large body of evidence to support the theory of global warming. And this body of evidence is growing all the time.

We could wait until the evidence is incontrovertible, but it would be folly to wait that long.

fits

piraka wrote:

How much of what you have quoted is due to natural processes and how much is due to increased CO2 in the troposphere?

Well why dont you look up the link yourself and have a good read of the IPCC report. Its all about 'confidences'. They either have a high, or very high confidence (I cant remember) that the observed changes are due in part to increased CO2. Its all very cautious (like all good science).

BTW I agree with Dudara, I'd be wary of labelling anything as fact.... although climate change is natural, and is a fact... the anthropogenic forcing is less certain.

piraka

fits wrote:

Well why dont you look up the link yourself and have a good read of the IPCC report. Its all about 'confidences'. They either have a high, or very high confidence (I cant remember) that the observed changes are due in part to increased CO2. Its all very cautious (like all good science).

Well...... I have read the summary report and the full scientific report and I am still not convinced that CO2 is the main driver of the observed global warming.

fits

piraka wrote:

Well...... I have read the summary report and the full scientific report

What? all of the 1000 odd pages? you've more stamina than I so.... I probably would read the hard copy.

and I am still not convinced that CO2 is the main driver of the observed global warming.

Maybe you need to go read the journals then if you have such an interest in the subject. I really dont know enough about the CO2 effect (I'm not a climatologist, or a physicist) but if a large group of scientific experts have a 'high confidence' in something I'm inclined to believe them myself (I know not everyone would).

fits

Actually *afterthought* can you (or anyone) point me in the direction of some good (preferably peer-reviewed) papers of dissent on the subject?

bonkey

piraka wrote:

Well...... I have read the summary report and the full scientific report and I am still not convinced that CO2 is the main driver of the observed global warming.

When you say "not convinced"...can you explain the scientific failings of the full scientific report which give rise to sufficient grounds to reject it?

Also, given that we don't have multiple planets to play with to test hypotheses, can you say what it would take to convince you of any model?

Regarding the OP's question...

GW is occurring. It has been observed for a number of years now. Thus, it is not inaccurate to say it is fact in that sense.

Facts, in the strictest sense, are observations, and are therefore bound to the past. Therefore, no-one should claim predictions as fact, regardless of the certainty we have. That said, many people claim predictions as fact, so its not really all that strange or unacceptable that Minister Gormley is suggesting that GW will continue in the immediate future (climatologically speaking). Even those who claim that its a natural phenomenon - some cycle or other, depending on what hypothesis they subscribe to - still accept that GW is not going to end this year or next. They merely differ in how long it will last, how severe it will be* and what we should do about it (if anything).

What the minister seemed to be suggesting, however, is that Anthropogenic Global Warming was established as fact, which is not the case. This is merely established with a high degree of certainty. It should be noted, though, that as a good politician (at least in your paraphrasing of him) he neglected to include the man-made rider on what he claimed as fact.

jc


* On an aside, isn't it amazing that not one critic of the theories fo Global Warming argues that their natural cycles say things will get worse? We hear arguments that the earth has been warmer in the past then even the models predict, but never are these arguments turned into the conclusion that these alleged cyclical causes will lead to a worse future.

brianthebard

dudara wrote:

Personally, I would not say something is fact (how do we know with absolute certainty? Theories are developed every day, it takes the test of time and the support of evidence for them to endure), but I will say that there is a large body of evidence to support the theory of global warming. And this body of evidence is growing all the time.

Thank you, this is what I'm talking about. Despite fits slightly insulting yawn seems to suggest, I am not actually questioning global warming, I am questioning the way people approach it and particularly the way it suits interest groups (which include the greens) to say that GW is "ACTUAL INCONTROVERTIABLE FACT" when in actuality there will always be some doubt and at the minute quite a bit.

fits

brianthebard wrote:

Despite fits slightly insulting yawn seems to suggest, .

Oh I yawned for lots of reasons.... many of which have nothing to do with you or your particular stance... so dont be insulted....

sarahirl

brianthebard wrote:

I am not actually questioning global warming, I am questioning the way people approach it and particularly the way it suits interest groups (which include the greens) to say that GW is "ACTUAL INCONTROVERTIABLE FACT" when in actuality there will always be some doubt and at the minute quite a bit.

how does it suit them? what profit do they stand to gain? i'm confused as to the logic of the argument here... is this becuase of the channel 4 documentary that said climate change is natural and subsequently which any scientist that was quoted threatened to sue the presenter of the programme becuase he misquoted them and used facts only up to the point it suited them?

i can understand why it suits many many companies and industries to deny climate change - oil, coal, gas, construction, etc etc - the list goes on and on and it'd make my fingers bleed to type it all out. the only industry i can see that it suits to say that climate change is a fact are environmental consultants and most of the work they do is more planning related than hippy tree hugging related.

also who doubts that climate change is a reality (note i didn't use the word fact)? politicians with vested interest in companies who have so far used the earths resources for free and are afraid of change?

please explain.

brianthebard

It suits interests groups if politicans endorse their claims, simple enough. It may seem like it suits those industries you've listed to deny climate change, but they are the same industries that are heavily advertising their green credentials and investing in green markets-look at any ads for shell, hsbc, toyota, etc in newsweek or national geographic and you'll see what I mean.

sarahirl

yes true it does suit interest groups for government to agree with them. but then again there's a massive difference between agreeing and pulling a u-turn in the way this society is run. for example if the government were serious about green issues then we would never have had the man made disaster in galway, wouldn't be building roads upon roads, would be building our houses to a passive standard or a high energy standard.

in regards to big companies claiming their green credentials. totally true. that type of advertising is everywhere - we're green, invest your money with us or buy our product. shell - past record not a great one, worst offences in nigeria (that i know of, there may be more). hsbc - used to work for them - they buy carbon credits and still invest people's money in non-ethical funds, in fact their ethical finance is only a small %. also what do they actually do? apart from invest in a few projects, buy carbon credits and implement cost cutting exercices (energy savings for example) in the buildings it's mostly lip service. please prove me wrong as i'd be more than delighted to hear that these companies are doing more than what is now becoming known as 'greenwash'.

even if you want to forget about the terms climate change, global warming, etc. just pretend those overused terms are not in existence, then surely you can agree that waste is a big issue in this country. our current landfill capacity is getting smaller year on year due to arguments over where new EU standard superdumps should be put. NIMBY! recycling - we don't create enough waste to build a facility in this country to recycle every piece of recyclable material so most gets shipped abroad which costs money as the price of fuel is ever increasing. then we try to borrow an idea from our European neighbours about incinerating and the controversy over that has been dragging on for over 10 years so much so that the first company pulled out.

if you take the water crisis in galway. it's well accepted that the assimilating capacity of Lough Corrib for waste (human sewage, animal slurry and other things we flush down the drains) was exceeded because the local authorities allowed a huge amount of housing to be built with no proper water treatment facility, houses were allowed to be built beside the lake and due to the porosity of the soil whatever went into their septic tank pretty much went straight into the lake (especially after the water level increased in the winter and washed out all the septic tanks). then you have the cattle which is where the cryptosporidium bug comes from. farmers were given grants which logically led farmers to have more cattle thereby receiving more grants. they were then told to have a certain type of shed (my knowledge is getting hazy for exact details here), which resulted in leakages into lough corrib. this type of outbreak has occurred in america and people died because people with depleted immune systems could not fight off the bug.

so ok, to hell with climate change, to hell with global warming... it's all bull! there are still issues with the basic way our society is run and governed in terms of an understanding of ecology, planning and seeing into the crystal ball with regards to decisions and their future impacts. if you take up these issues, then by all means i would applaud you. but please don't dimiss all of the issues going on in ireland to do with the environment just because you're sick of hearing about climate change and global warming.

brianthebard

sarahirl wrote:

yes true it does suit interest groups for government to agree with them. but then again there's a massive difference between agreeing and pulling a u-turn in the way this society is run. for example if the government were serious about green issues then we would never have had the man made disaster in galway, wouldn't be building roads upon roads, would be building our houses to a passive standard or a high energy standard.

in regards to big companies claiming their green credentials. totally true. that type of advertising is everywhere - we're green, invest your money with us or buy our product. shell - past record not a great one, worst offences in nigeria (that i know of, there may be more). hsbc - used to work for them - they buy carbon credits and still invest people's money in non-ethical funds, in fact their ethical finance is only a small %. also what do they actually do? apart from invest in a few projects, buy carbon credits and implement cost cutting exercices (energy savings for example) in the buildings it's mostly lip service. please prove me wrong as i'd be more than delighted to hear that these companies are doing more than what is now becoming known as 'greenwash'.

even if you want to forget about the terms climate change, global warming, etc. just pretend those overused terms are not in existence, then surely you can agree that waste is a big issue in this country. our current landfill capacity is getting smaller year on year due to arguments over where new EU standard superdumps should be put. NIMBY! recycling - we don't create enough waste to build a facility in this country to recycle every piece of recyclable material so most gets shipped abroad which costs money as the price of fuel is ever increasing. then we try to borrow an idea from our European neighbours about incinerating and the controversy over that has been dragging on for over 10 years so much so that the first company pulled out.

My argument was never that global warming doesn't exist or that we shouldn't try and live in a more environmentally friendly manner. My problem was with the way people such as minister gormley approach the concept. Calling something undeniable fact suggests strongly that one is unwilling to look at alternative points of view, which is counter productive.

p.s. hsbc have actually been using ads which say there are the first carbon neutral bank since 2006, which I found hard to believe, so the fact that you know they buy carbon credits shows how green they really are.

Sponge Bob

Its a fact , I have no problem with John Gormley if he proceeds with his plans on the assumption that its a fact .

Sam Kade

Maggie Thacther started this global warming nonsense back in 1986 to close down coal mines is she a climate scientist? Think about it they are saying that Co2 is the cause, the ozone hole is over the antartic with a smaller hole over the artic so the Co2 that is produced in every country makes it's way to the antartic then ascends to cause a hole in the ozone. If that isn't enough nonsense the sun will have to move from it's position to shine through the hole. Common sense will tell you that if Co2 causes the ozone to evaporate then there should be a lot of holes over the most polluting countries. Ozone doesn't protect us from the sun it's a layer that is formed when air from the earth meets the suns rays it's constantly being destroyed and reproduced. I am all for cutting emissions and I do my part but this global warming nonsense is going too far.

Lennoxschips

The ozone hole and global warming are too completely unrelated things.

Ozone depletion is caused by CFCs, not CO2.

Sam Kade

Ozone depletion was caused by CFC's they were banned in 1991.

mrgalway

In my opinion:

It is getting warmer (not sure if its due to global warming or not but the polar regions are melting)
We are putting out more and more CO2 each year at an increasing rate. The Chineese and Indians are about to jack up that rate considerably.
There is not a damn thing we can do about it unless we all decide to live in poverty.

The Chessplayer

brianthebard wrote: »

A while ago minister Gormley stated that the time for debate is over and that global warming is now undeniable fact. (Not a direct quote). However even if the evidence is extremely strong surely it is important that people not start to be jump the gun and pronounce things to be fact that scientifically or actually speaking, aren't yet fact?

What are you asking here? Does this question concern correct use of grammar, or are you asking about global warming?

If the answer is the former then I would say:

It is right to say that global warming is a fact.

gerky

Sam Kade wrote: »

Ozone depletion was caused by CFC's they were banned in 1991.

CFC'S are still in limited use but are due to be fully phased out by 2010.
Co2 and other greenhouse gases don't stay in a certain spot as they are not solids just as oxygen doesn't stay in a certain spot if it did we'd be in trouble.
And no Maggie thatcher didn't start talk about global warming.

Capt'n Midnight

Sam Kade wrote: »

Ozone depletion was caused by CFC's they were banned in 1991.

1991 eh?
http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=514&ArticleID=5624&l=en

Chiangshou,China 1 July 2007 - China, the world's largest producer of chlorofluorocarbons (CFC) and halon, today shut down five of its six remaining plants, putting the country two and a half years ahead of the Montreal Protocol's 2010 deadline for phase-out of the two ozone depleting chemicals.
...
The closure of the Chinese plants now puts India and South Korea as leading producers of the two ozone depleting chemicals in Asia Pacific, with a remaining combined production level of about 15,000 m/tons

not too sure if India are still in the cfc business.




Global Warming is happening FACT
Increased CO2 levels can cause global warming FACT
Global Warming is entirely caused by human CO2 emissions NOT PROVEN
Human CO2 emissions would make any natural Global Warming worse FACT

Sam Kade

Capt'n Midnight wrote: »

1991 eh?
http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=514&ArticleID=5624&l=ennot too sure if India are still in the cfc business.




Global Warming is happening FACT
Increased CO2 levels can cause global warming FACT
Global Warming is entirely caused by human CO2 emissions NOT PROVEN
Human CO2 emissions would make any natural Global Warming worse FACT

Are you a climate scientist?

Macha

Just to throw in my 2 cents worth, if you ready the IPCC report, the words 'may' 'probably' and 'likely' are bandied about a fair bit It sounds a lot like those ads for All Bran, that tell you it 'MAY' help with heart disease etc..

I hope no one shoots me down for referencing Wikipedia but if you look here, you'll see that the most powerful greenhouse gas is actually water vapour:

http://en.wikipedia.org/wiki/Greenhouse_gas

Now I would be really interested to see a study into the causes of an increase in water vapour...

In addition, the main argument for anthropogenic global warming is that the world's temperature has never increased at the rate it is doing so today (and thus connecting it to human caused increases in co2 emissions). I would argue that we just don't know how fast the temperature has increased in the world's history. That is information we just don't have.

Scofflaw

Sam Kade wrote: »

Global Warming is happening FACT
Increased CO2 levels can cause global warming FACT
Global Warming is entirely caused by human CO2 emissions NOT PROVEN
Human CO2 emissions would make any natural Global Warming worse FACT

Are you a climate scientist?

Actually, the essential science behind the anthropogenic climate effect is pretty approachable (I'm BSc Geology, MSc Environmental Resource Management, now in IT):

1. carbon dioxide causes a 'greenhouse' effect - known since the 19th century, easily experimentally proven.

2. Earth's atmospheric carbon dioxide and other greenhouse gases are responsible for the planet not being at -18 degrees. Again, this is uncontroversial - similar effects are observable on Mars and Venus.

3. Earth's atmospheric carbon dioxide forms part of one of the major geochemical cycles - the Carbon cycle. With no interference (human or geological), this cycle takes out of the atmosphere roughly as much carbon as enters it.

4. human industry produces carbon dioxide over and above natural production by about 5%

5. this additional carbon dioxide entering the atmosphere is not compensated for by additional carbon dioxide exiting - the carbon cycle is not running any faster

6. the carbon dioxide from industry therefore builds up in the atmosphere, producing the observed rising atmospheric carbon dioxide levels

7. refer back to step 1

What's tricky is modelling the results of any given rise in carbon dioxide.

cordially,
Scofflaw

Scofflaw

taconnol wrote: »

Just to throw in my 2 cents worth, if you ready the IPCC report, the words 'may' 'probably' and 'likely' are bandied about a fair bit It sounds a lot like those ads for All Bran, that tell you it 'MAY' help with heart disease etc..

Each of those words have a specific definition:

Probability of occurrence:
virtually certain - more than 99%
extremely likely - more than 95%
very likely - more than 90%
likely - more than 60%
more likely than not - more than 50%
unlikely - less than 33%
very unlikely - less than 10%
extremely unlikely - less than 5%

taconnol wrote: »

I hope no one shoots me down for referencing Wikipedia but if you look here, you'll see that the most powerful greenhouse gas is actually water vapour:

http://en.wikipedia.org/wiki/Greenhouse_gas

Now I would be really interested to see a study into the causes of an increase in water vapour...

Water vapour is well-studied. Its residence in the atmosphere is extremely short-term, and the only driver is ocean temperature. Warmer oceans mean more water vapour, but you have to warm the oceans first.

taconnol wrote: »

In addition, the main argument for anthropogenic global warming is that the world's temperature has never increased at the rate it is doing so today (and thus connecting it to human caused increases in co2 emissions). I would argue that we just don't know how fast the temperature has increased in the world's history. That is information we just don't have.

We certainly do have such information - from ice cores, from glacial varves, from pollen records, tree rings, and a huge number of other sources. There are an amazing number of organisms that display temperature-sensitive behaviour, and leave behind very well-known remains. Palaeo-temperature (and palaeo-climate) reconstruction is a pretty exact science.

cordially,
Scofflaw

Macha

Scofflaw wrote: »

Each of those words have a specific definition:

No doubt they do. That's not my point. My point is even the IPCC is not 100% and it is bad scientific procedure to jump on the bandwagon and ignore the 1%, 2%, 5% possibility that they are wrong.

Scofflaw wrote: »

Water vapour is well-studied. Its residence in the atmosphere is extremely short-term, and the only driver is ocean temperature. Warmer oceans mean more water vapour, but you have to warm the oceans first.

It's residence in the atmosphere may be short-term but it is still the primary greenhouse gas.

Scofflaw wrote: »

We certainly do have such information - from ice cores, from glacial varves, from pollen records, tree rings, and a huge number of other sources. There are an amazing number of organisms that display temperature-sensitive behaviour, and leave behind very well-known remains. Palaeo-temperature (and palaeo-climate) reconstruction is a pretty exact science.

I'm afraid it is notan exact science. Again, to quote wikipedia (purely for convenience-I can get from another source if necessary):

http://en.wikipedia.org/wiki/Ice_core

"The length of the record depends on the depth of the ice core and varies from a few years up to 800 kyr for the EPICA core. The time resolution (i.e. the shortest time period which can be accurately distinguished) depends on the amount of annual snowfall, and reduces with depth as the ice compacts under the weight of layers accumulating on top of it. Upper layers of ice in a core correspond to a single year or sometimes a single season. Deeper into the ice the layers thin and annual layers become indistinguishable."

Getting an ice core (of which only 2 exist) is not just a simple matter of drilling a hole in the ice and pulling it out. Ice shifts sideways from pressure of above, a huge amount of calculations have to go into trying to decipher it. My point: we just cannot say that the world's temperature as ever increased at the rate it is doing today

Scofflaw

taconnol wrote: »

No doubt they do. That's not my point. My point is even the IPCC is not 100% and it is bad scientific procedure to jump on the bandwagon and ignore the 1%, 2%, 5% possibility that they are wrong.

There's virtually nothing in science that is 100%.

taconnol wrote: »

It's residence in the atmosphere may be short-term but it is still the primary greenhouse gas.

It remains a secondary effect. The short residence time means that effects quickly dissipate, and the fact that it's driven by warming in the first place means that it cannot be a primary cause of warming.

taconnol wrote: »

I'm afraid it is notan exact science. Again, to quote wikipedia (purely for convenience-I can get from another source if necessary):

http://en.wikipedia.org/wiki/Ice_core

"The length of the record depends on the depth of the ice core and varies from a few years up to 800 kyr for the EPICA core. The time resolution (i.e. the shortest time period which can be accurately distinguished) depends on the amount of annual snowfall, and reduces with depth as the ice compacts under the weight of layers accumulating on top of it. Upper layers of ice in a core correspond to a single year or sometimes a single season. Deeper into the ice the layers thin and annual layers become indistinguishable."

Getting an ice core (of which only 2 exist) is not just a simple matter of drilling a hole in the ice and pulling it out. Ice shifts sideways from pressure of above, a huge amount of calculations have to go into trying to decipher it. My point: we just cannot say that the world's temperature as ever increased at the rate it is doing today

Er, no, there are hundreds, from all over the world - Dye 3, GRIP, GRISP, NGRIP, Vostok, EPICA, Dome F are the most prominent deep cores - and Kilimajaro, the Andes, the Himalayas, the Guliya ice cap in China - and ice cores are only one method of getting temperature proxies. There are plenty of others, available at a bog near you, in pollen records. Tree ring records also go back up to 10,000 years in various locations.

Your point perhaps suffers from not having done palaeo-climate reconstructions as part of your undergraduate and post-graduate degrees?

Also, if you're going to quote from sources, please quote the full context. Your quote:

"Upper layers of ice in a core correspond to a single year or sometimes a single season. Deeper into the ice the layers thin and annual layers become indistinguishable."

is immediately followed by:

"An ice core from the right site can be used to reconstruct an uninterrupted and detailed climate record extending over hundreds of thousands of years, providing information on a wide variety of aspects of climate at each point in time."

In other words, the problem outlined in your quote is clearly a soluble one. It's as if you quoted a bit of text that said:

"There are many problems with dating organic material"

but failed to include the following piece:

", but nearly all of them have been resolved."

cordially,
Scofflaw

Capt'n Midnight

Water vapour is self regulating to a certain extent.
More vapour means more clouds.
Clouds being white reflect more solar radiation than land or sea would and so there is less heating that there would otherwise be.

A bit like daisyworld , but without the daisy's

brianthebard

taconnol wrote: »

No doubt they do. That's not my point. My point is even the IPCC is not 100% and it is bad scientific procedure to jump on the bandwagon and ignore the 1%, 2%, 5% possibility that they are wrong.




It's residence in the atmosphere may be short-term but it is still the primary greenhouse gas.




I'm afraid it is notan exact science. Again, to quote wikipedia (purely for convenience-I can get from another source if necessary):

http://en.wikipedia.org/wiki/Ice_core

"The length of the record depends on the depth of the ice core and varies from a few years up to 800 kyr for the EPICA core. The time resolution (i.e. the shortest time period which can be accurately distinguished) depends on the amount of annual snowfall, and reduces with depth as the ice compacts under the weight of layers accumulating on top of it. Upper layers of ice in a core correspond to a single year or sometimes a single season. Deeper into the ice the layers thin and annual layers become indistinguishable."

Getting an ice core (of which only 2 exist) is not just a simple matter of drilling a hole in the ice and pulling it out. Ice shifts sideways from pressure of above, a huge amount of calculations have to go into trying to decipher it. My point: we just cannot say that the world's temperature as ever increased at the rate it is doing today

Thank god someone gets it.

Lennoxschips

CO2 molecules are roughly the same size as the wavelength of infrared radiation being radiated from the Earth's surface. So instead of all of this infrared radiation escaping back into space again, it hits the CO2 molecules and causes them to vibrate, converting it to kinetic and heat energy, and retaining it in the atmosphere. As Scofflaw correctly points out, this CO2 in the atmosphere is responsible for keeping us as warm as we are in the first place. Otherwise we'd be a ball of ice. But just as the planet would freeze without CO2, add more and it will warm up. There is nothing controversial about this. It's a simple process that any chemist or physicist will explain.

I don't like getting involved in these debates really because I don't see what there is to debate. Well, I guess the only thing left to talk about is just how much warming we'll see...

Just out of interest scofflaw, where did you do your MSc in ERM?

Capt'n Midnight

google for snowball earth to see what happened when there was very little CO2 in the air in times past.

New Scientist reckon that the amount of CO2 in the atmosphere now will delay the next ice age by half a million years. That's the next one caused by cyclic changes in the earths orbit. Also the removal mechanism for the CO2 was rock weathering. So if we mine more would it help, not really since its a very slow mechanism.

Capt'n Midnight

Proof of global warming.

Macha

Scofflaw wrote: »

There's virtually nothing in science that is 100%.

My point is that there IS doubt and that it is bad scientific practice to ignore the small % of doubt and just go with the flow. If everyone just jumped on the bandwagon all the time we would still be believing that the earth was flat. I also don't like the perception in the media that 100% of scientists are 100% agreed about the anthropogenic causes of global warming. It isn't true and it's misleading.

Scofflaw wrote: »

It remains a secondary effect. The short residence time means that effects quickly dissipate, and the fact that it's driven by warming in the first place means that it cannot be a primary cause of warming.

I agree. Water vapour is caused by something else-It doesn't just happen by itself. Perhaps it is caused by an increase of C02 or perhaps its caused by increased solar activity. I would be interested to see any studies on the cause of increased water vapour. Nevertheless if it is the most active greenhouse gas, it deserves a bit more attention. Everyone is fixated on C02. What about methane? It is 8 times more potent a greenhouse gas than C02.

Scofflaw wrote: »

Er, no, there are hundreds, from all over the world - Dye 3, GRIP, GRISP, NGRIP, Vostok, EPICA, Dome F are the most prominent deep cores - and Kilimajaro, the Andes, the Himalayas, the Guliya ice cap in China - and ice cores are only one method of getting temperature proxies.

Maybe I didn't make myself clear. The graph in question that is used to support the link between temperatures and CO2 in the atmosphere comes from just 2 ice cores: EPICA and Vostok.

Scofflaw wrote: »

There are plenty of others, available at a bog near you, in pollen records. Tree ring records also go back up to 10,000 years in various locations.

These records are largely irrelevant, particularly if they come from Ireland. They only go back 10,000 years. This only goes back to the end of the last glacial period, not even the last ice age! We need records that much further back in time than a mere 10,000 years.

Scofflaw wrote: »

Also, if you're going to quote from sources, please quote the full context.

That's why I put the link...

Scofflaw wrote: »

Your quote:

"Upper layers of ice in a core correspond to a single year or sometimes a single season. Deeper into the ice the layers thin and annual layers become indistinguishable."

is immediately followed by:

"An ice core from the right site can be used to reconstruct an uninterrupted and detailed climate record extending over hundreds of thousands of years, providing information on a wide variety of aspects of climate at each point in time."

In other words, the problem outlined in your quote is clearly a soluble one. It's as if you quoted a bit of text that said:

"There are many problems with dating organic material"

but failed to include the following piece:

", but nearly all of them have been resolved."

SOrry I don't follow how you can extrapolate your ideas from these two quotes. The wikipedia page certainly does not say that the problems with dating organic material have been resolved. If you actually read the whole wikipedia article, you will see just how complex the dating and management of these ice cores are. It is not an exact science and none of the scientists working on them would ever claim that it is.

Lennoxschips

I also don't like the perception in the media that 100% of scientists are 100% agreed about the anthropogenic causes of global warming. It isn't true and it's misleading.

Can you find a published article in a scientific journal that shows that anthropogenic GHG emissions are not contributing to global warming?

I agree. Water vapour is caused by something else-It doesn't just happen by itself. Perhaps it is caused by an increase of C02 or perhaps its caused by increased solar activity. I would be interested to see any studies on the cause of increased water vapour. Nevertheless if it is the most active greenhouse gas, it deserves a bit more attention. Everyone is fixated on C02. What about methane? It is 8 times more potent a greenhouse gas than C02.

Industrialisation is not causing significant water vapour emissions. What about methane? Methane is a greenhouse gas. Scientists also study methane emissions. Methane emissions are also covered by the Kyoto treaty, just like other known greenhouse gases are. CO2 is the most common, so gets the most mainstream media coverage, but, believe me, all greenhouse gases are studied.

Maybe I didn't make myself clear. The graph in question that is used to support the link between temperatures and CO2 in the atmosphere comes from just 2 ice cores: EPICA and Vostok.

And a couple in Greenland as well. And the temperature changes noted are present in hundreds of ocean sediment cores as well.

Scofflaw

Lennoxschips wrote: »

CO2 molecules are roughly the same size as the wavelength of infrared radiation being radiated from the Earth's surface. So instead of all of this infrared radiation escaping back into space again, it hits the CO2 molecules and causes them to vibrate, converting it to kinetic and heat energy, and retaining it in the atmosphere. As Scofflaw correctly points out, this CO2 in the atmosphere is responsible for keeping us as warm as we are in the first place. Otherwise we'd be a ball of ice. But just as the planet would freeze without CO2, add more and it will warm up. There is nothing controversial about this. It's a simple process that any chemist or physicist will explain.

I don't like getting involved in these debates really because I don't see what there is to debate. Well, I guess the only thing left to talk about is just how much warming we'll see...

Yes - it's not as if arguing about it will make it go away! The theory is that the more people are convinced by the 'skeptics' the less political will there will be to do anything the oil companies don't want.

Lennoxschips wrote: »

Just out of interest scofflaw, where did you do your MSc in ERM?

Edinburgh.

cordially,
Scofflaw

Macha

Lennoxschips wrote: »

Can you find a published article in a scientific journal that shows that anthropogenic GHG emissions are not contributing to global warming?

Hmm I suppose what I'm arguing isn't that human's arent contributing to global warming, but that we cannot be sure of how much we are contributing. Resouces are finite and as such, I would argue that it is wiser to invest in protecting against the effects of global warming than pumping much needed funds into paying Kyoto fines and spending huge amounts on carbon credits. We need to stop building in floodplains, etc...

As a contrast, I fully support Ireland's inevitable fines from the EU on our appaling water quality in 2015. It will give us the kick up the arse we need to sort out our septic tank problem (among other things). Here, however, there is no doubt that the water quality problem is our fault. It's clear in the testing of waters that show the coliform pollution etc, that it is either coming from human or animal faeces.

Lennoxschips wrote: »

Industrialisation is not causing significant water vapour emissions. What about methane? Methane is a greenhouse gas. Scientists also study methane emissions. Methane emissions are also covered by the Kyoto treaty, just like other known greenhouse gases are. CO2 is the most common, so gets the most mainstream media coverage, but, believe me, all greenhouse gases are studied.

Ok I take your point. But why then, is water vapour not discussed in the latest IPCC report? OK it can be argued that it is secondary but surely we should giving at least a nod to the gas that may be contributing up to 70% of the green house effet?

Lennoxschips wrote: »

And a couple in Greenland as well. And the temperature changes noted are present in hundreds of ocean sediment cores as well.

I have no doubt that they do - but to a high level of detail going back thousands and thousands of years? I mean the change that a lot of this is based on has only happened in the last 50 years. Can we really say that the earth has never had this rate of temperature growth over a 50 year period ever??

Scofflaw

taconnol wrote: »

My point is that there IS doubt and that it is bad scientific practice to ignore the small % of doubt and just go with the flow. If everyone just jumped on the bandwagon all the time we would still be believing that the earth was flat.

Hmm. So the way the IPCC quantifies its doubts doesn't appeal? No, I accept your point - stifling dissent, or pretending that there is no doubt, is not useful. However, to go on to your next point...

taconnol wrote: »

I also don't like the perception in the media that 100% of scientists are 100% agreed about the anthropogenic causes of global warming. It isn't true and it's misleading.

...well, 99.9% then. Again, the impression given by the media is deeply misleading. The scientific community has no problem saying "well, we don't know that" or "there's no proven link", but the media is interested in reporting a 'two-sided fight'. A good example would be the link between global warming and hurricanes - which came up last summer. Some of the media reported that there was a link, some reported that a claimed link had been debunked. Looking around the scientific reports, people said they were investigating a link, and a couple offered their personal opinion that it "made sense". Out of that candle flame came a huge amount of media smoke - naturally enough, because the hurricanes were attention-grabbing.

Those with a specific political agenda to push, of course, are even worse - mostly socialists who see climate change as a way of pushing a socialist agenda.

However, the consensus is not a media artefact, and the number of relevantly qualified dissenting scientists is very small.

taconnol wrote: »

I agree. Water vapour is caused by something else-It doesn't just happen by itself. Perhaps it is caused by an increase of C02 or perhaps its caused by increased solar activity. I would be interested to see any studies on the cause of increased water vapour. Nevertheless if it is the most active greenhouse gas, it deserves a bit more attention. Everyone is fixated on C02. What about methane? It is 8 times more potent a greenhouse gas than C02.

Nearly everything in the media is quoted as CO2, but the scientific literature usually talks in terms of CO2-equivalent. Methane is not negligible, as you say, and it certainly isn't ignored - any "CO2 balance" calculated for something like forestry takes all known greenhouse gases into account - and globally the relevant contribution of each is well mapped out.

Lists of greenhouse gases and their CO2 equivalent are available online - I'm pretty sure Wikipedia has them. Otherwise, look for the IPCC reports, they're in one of the Annexes.

Politically, though, methane is touchy, because the main emitter is agriculture - which means going head to head with the farmers...not a popular choice for politicians.

taconnol wrote: »

Maybe I didn't make myself clear. The graph in question that is used to support the link between temperatures and CO2 in the atmosphere comes from just 2 ice cores: EPICA and Vostok.

See Lennoxschips point...do you actually think the whole science of climate change is founded on just two ice cores? There are dozens of temperature proxy measures, and atmospheric CO2 is well known over the timescale of carbon-dating (because atmospheric CO2 variation affects the dating).

taconnol wrote: »

These records are largely irrelevant, particularly if they come from Ireland. They only go back 10,000 years. This only goes back to the end of the last glacial period, not even the last ice age! We need records that much further back in time than a mere 10,000 years.

Any particular reason why? Is 10,000 years not long enough?

taconnol wrote: »

That's why I put the link...

SOrry I don't follow how you can extrapolate your ideas from these two quotes. The wikipedia page certainly does not say that the problems with dating organic material have been resolved. If you actually read the whole wikipedia article, you will see just how complex the dating and management of these ice cores are. It is not an exact science and none of the scientists working on them would ever claim that it is.

Perhaps that wasn't clear - my apologies. It reminds me of a standard trick by Creationists, which is to take a partial quote from a source ("there are problems with carbon dating...") which appears to bolster their case, leaving off the bit that says "...fortunately, they're all soluble". I was using dating as an example of that technique, rather than making a point about ice cores.

I'm well aware that ice core reconstruction is not an exact science, and if you look, that's not what I said. "Palaeo-temperature (and palaeo-climate) reconstruction is a pretty exact science" is my claim, and I have no reason to change it, because that's the case.

The problems involved in interpreting ice cores are not insoluble either. If they were, there would be no point in drilling them in the first place. However, the uncertainties are certainly large enough that we can't place a 'deep' date better than a couple of centuries in a good core, or better than a few millennia in others such as Vostok.

Does that prevent us tracking rapid changes in temperature, and correlating them with CO2? No, because we know that the climate fluctuated halfway from ice age to 'modern' conditions over years or decades at the end of the last ice age. A lecture I attended at the RIA mentioned a figure of roughly 25 years for a switch from non-glacial to fully glacial conditions, which the lecturer correlated with a shutdown of the Gulf Stream.

That's the important point about cross-correlation of multiple sources - errors are divided, not multiplied, which means that multiple low-resolution sources yield precise results.

cordially,
Scofflaw

Scofflaw

taconnol wrote: »

Hmm I suppose what I'm arguing isn't that human's arent contributing to global warming, but that we cannot be sure of how much we are contributing. Resouces are finite and as such, I would argue that it is wiser to invest in protecting against the effects of global warming than pumping much needed funds into paying Kyoto fines and spending huge amounts on carbon credits. We need to stop building in floodplains, etc...

It's true that we don't know exactly how much of the warming we're producing, if by exact you mean decimal places and no disagreement whatsoever. On the other hand, most of the other possible contributors have been studied, and their effect modelled. Subtracting those gives a measure of the human contribution. More worryingly, though, we don't know how severe the repercussions will be in any exact sense either, so it makes sense both to try and limit what we're doing as well as preparing for possible consequences.

taconnol wrote: »

Ok I take your point. But why then, is water vapour not discussed in the latest IPCC report? OK it can be argued that it is secondary but surely we should giving at least a nod to the gas that may be contributing up to 70% of the green house effet?

It forms part of most climate models, so it's assumed in the predictions of the IPCC, but it isn't an independent variable, so it isn't discussed.

taconnol wrote: »

I have no doubt that they do - but to a high level of detail going back thousands and thousands of years? I mean the change that a lot of this is based on has only happened in the last 50 years. Can we really say that the earth has never had this rate of temperature growth over a 50 year period ever??

GISP and GISP2 give annual resolution for 110,000 years (Alley, Vol. 97, Issue 4, 1331-1334, February 15, 2000 Proc.Nat Acad. Sci.). These show large swings over short periods, so the climate certainly has changed abruptly before, and those abrupt changes follow rapid changes in (particularly) atmospheric CO2 and insolation. The upward changes are not as sharp as this one - the northern Atlantic climate can go down sharply, but doesn't go up as quickly.

Do you feel that the existence of previous large natural temperature swings means automatically that this one is also natural?

cordially,
Scofflaw

Macha

Scofflaw wrote: »

...well, 99.9% then. Again, the impression given by the media is deeply misleading. The scientific community has no problem saying "well, we don't know that" or "there's no proven link", but the media is interested in reporting a 'two-sided fight'. A good example would be the link between global warming and hurricanes - which came up last summer. Some of the media reported that there was a link, some reported that a claimed link had been debunked. Looking around the scientific reports, people said they were investigating a link, and a couple offered their personal opinion that it "made sense". Out of that candle flame came a huge amount of media smoke - naturally enough, because the hurricanes were attention-grabbing.

Those with a specific political agenda to push, of course, are even worse - mostly socialists who see climate change as a way of pushing a socialist agenda.

Yes - it's an unfortunate irony that the more is at stake, usually the more people there are that try to muddy the waters. And there is as much as stake on the pro-anthroprogenic (for want of a better word) side as the other side. It is much easier to convince people to use their cars less, etc etc when you have something like GW to push that argument. Of course people should be using their cars less even if C02 isn't the main factor in GW (Cars are unsociable, polluting, cause congestion, don't exercise the occupants etc) but it's much easier to make that argument when you can also link driving your car to GW.

I have to say, it doesn't help when George Bush with his obvious links to oil stands up and says there is no link between GW and human activity :rolleyes: For those who haven't seen Will Ferrell's take on Geoge Bush's stance on GW, very, very funny:

http://www.funnyordie.com/videos/3830

Scofflaw wrote: »

However, the consensus is not a media artefact, and the number of relevantly qualified dissenting scientists is very small.

True the majority would agree that GW is caused by human activity but I would argue that scientists who argue against AGW will find it difficult to get funding. My lecturer used the example of acid rain in the early 90s. He said that they all studied acid rain because that's where the money was, that's what they got funding to study. In a similar fashion, I don't think much funding and thus much study is going into the alternative view of GW. And my guess is that the only ones really studying this area are those with vested interests ie the oil companies. Even I would probably be very skeptical of any study by an oil company but then again, it wouldn't necessarily be wrong.

Scofflaw wrote: »

Nearly everything in the media is quoted as CO2, but the scientific literature usually talks in terms of CO2-equivalent. Methane is not negligible, as you say, and it certainly isn't ignored - any "CO2 balance" calculated for something like forestry takes all known greenhouse gases into account - and globally the relevant contribution of each is well mapped out.

Lists of greenhouse gases and their CO2 equivalent are available online - I'm pretty sure Wikipedia has them. Otherwise, look for the IPCC reports, they're in one of the Annexes.

Ok thanks for that.

Scofflaw wrote: »

Politically, though, methane is touchy, because the main emitter is agriculture - which means going head to head with the farmers...not a popular choice for politicians.

Yes, thank god for the EU and the Nitrates Directive. We're being dragged kicking and screaming into the 21st century. It funny - the number of people actually employed in agriculture is a v small percentage but they have such a strong lobby. If you look at the planning laws for agricultural land, you basically have free reign to build almost anything you want - without even having to apply for planning permission - crazy.

Scofflaw wrote: »

See Lennoxschips point...do you actually think the whole science of climate change is founded on just two ice cores? There are dozens of temperature proxy measures, and atmospheric CO2 is well known over the timescale of carbon-dating (because atmospheric CO2 variation affects the dating).

Any particular reason why? Is 10,000 years not long enough?

Well again, the main crux of the AGW argument is that the rate of climate change is unprecedented. The history of the earth is a lot lonver than 10,000. We need to go back much further than 10,000 years.

Also, have you fond a good explanation for the temperature increase from around 1915 to 1940 for which there is no corresponding increase in C02 output? There is a strong correlation between the temperature increase and the increase in C02 output from 1950 to present but I have not heard a good one for the 1915-1940.

Scofflaw wrote: »

Perhaps that wasn't clear - my apologies. It reminds me of a standard trick by Creationists, which is to take a partial quote from a source ("there are problems with carbon dating...") which appears to bolster their case, leaving off the bit that says "...fortunately, they're all soluble". I was using dating as an example of that technique, rather than making a point about ice cores.

I'm well aware that ice core reconstruction is not an exact science, and if you look, that's not what I said. "Palaeo-temperature (and palaeo-climate) reconstruction is a pretty exact science" is my claim, and I have no reason to change it, because that's the case.

The problems involved in interpreting ice cores are not insoluble either. If they were, there would be no point in drilling them in the first place. However, the uncertainties are certainly large enough that we can't place a 'deep' date better than a couple of centuries in a good core, or better than a few millennia in others such as Vostok.

Does that prevent us tracking rapid changes in temperature, and correlating them with CO2? No, because we know that the climate fluctuated halfway from ice age to 'modern' conditions over years or decades at the end of the last ice age. A lecture I attended at the RIA mentioned a figure of roughly 25 years for a switch from non-glacial to fully glacial conditions, which the lecturer correlated with a shutdown of the Gulf Stream.

That's the important point about cross-correlation of multiple sources - errors are divided, not multiplied, which means that multiple low-resolution sources yield precise results.

Hmm so you're saying there have been very rapid climate changes in the past, documented? And not caused by humans? Sorry I've only just started studying this so am not aware of all relevant info

Macha

Scofflaw wrote: »

Do you feel that the existence of previous large natural temperature swings means automatically that this one is also natural?

Not at all but the word 'unprecedented' gets bandied around a lot and well, I guess I don't like this idea in the green movement that once upon a time a perfect 'Eden' existed and we are now destroying it. What a lot of people don't understand is that climate change is a natural phenomenon. Even if you look at managed habitats - you can't just go away and leave them - they will change. If you want them to stay the way they are, you have to manage them

Am I making any sense?

Lennoxschips

The problem with the the climate sceptic arguments is that they are like Bertie Ahern's Mahon statements, i.e., they keep changing.

At first they denied that the Earth was warming at all, despite global observed temperature climbing at record rates. Then when it became pretty damn obvious that that the Earth was indeed warming, they started saying it was natural and that it wasn't us. Now it's getting obvious that it is us, and you can see signs of their next tactic already: it won't be too bad, we'll adapt etc.

Hmm so you're saying there have been very rapid climate changes in the past, documented? And not caused by humans?

Yes, of course there have been. But each of these have a logical explanation. A change of orbit around the sun, a volcanic explosion, a sudden massive discharge of methane from a natural source, a sudden breakup of ice-age ice sheets, a meteor impact, etc.. None of those things are being observed now.

Scofflaw

First off, I'm just going to say that it's a pleasure to discuss this with someone whose doubts are rational. It is an experience all too rare.

taconnol wrote: »

Yes - it's an unfortunate irony that the more is at stake, usually the more people there are that try to muddy the waters. And there is as much as stake on the pro-anthroprogenic (for want of a better word) side as the other side. It is much easier to convince people to use their cars less, etc etc when you have something like GW to push that argument. Of course people should be using their cars less even if C02 isn't the main factor in GW (Cars are unsociable, polluting, cause congestion, don't exercise the occupants etc) but it's much easier to make that argument when you can also link driving your car to GW.

Yes, I certainly wouldn't deny that. However, the argument doesn't quite hold up, because those groups generally have nothing to do with the science of climate change. If you develop cancer, and a fundamentalist tries to persuade you it is in judgement for your sins, you still have cancer, as diagnosed by a doctor.

taconnol wrote: »

I have to say, it doesn't help when George Bush with his obvious links to oil stands up and says there is no link between GW and human activity :rolleyes: For those who haven't seen Will Ferrell's take on Geoge Bush's stance on GW, very, very funny:

http://www.funnyordie.com/videos/3830

Being able to satirise GW is quite a feat...

taconnol wrote: »

True the majority would agree that GW is caused by human activity but I would argue that scientists who argue against AGW will find it difficult to get funding. My lecturer used the example of acid rain in the early 90s. He said that they all studied acid rain because that's where the money was, that's what they got funding to study. In a similar fashion, I don't think much funding and thus much study is going into the alternative view of GW. And my guess is that the only ones really studying this area are those with vested interests ie the oil companies. Even I would probably be very skeptical of any study by an oil company but then again, it wouldn't necessarily be wrong.

Hmm. Climate change research is where the money is in climate science, yes. However, the study of climate change is the study of climate, whether you're funded by a 'neutral' source like the UK government, or by a pressure group of either persuasion. Did your lecturer say "the money was in proving that acid rain was the result of SO2 emissions by industry"?

A climate scientist who decides to study the possibility of a link between climate change and hurricanes does not study something different from a scientist who wishes to prove there is or isn't a link. Short of actually faking the results, therefore, all that any of our three putative scientists can do is shade the conclusions.

Further, this ignores the issue that most science funding is governmental or industrial. Neither governments nor industry have been keen to hear bad news.

taconnol wrote: »

Yes, thank god for the EU and the Nitrates Directive. We're being dragged kicking and screaming into the 21st century. It funny - the number of people actually employed in agriculture is a v small percentage but they have such a strong lobby. If you look at the planning laws for agricultural land, you basically have free reign to build almost anything you want - without even having to apply for planning permission - crazy.

What can I do but agree. I worked for the Groundwater Department of the GSI for a while in the 90's (after the Nitrates Directive was issued by the EU), and the contamination of groundwater by unlined slurry pits, septic tanks, and runoff, was depressing.

taconnol wrote: »

Well again, the main crux of the AGW argument is that the rate of climate change is unprecedented.

Hmm. No, that's not the case. Rapid fluctuations observed in the palaeo-temperature record are all associated with the beginning and end of ice ages. Unless we are actually entering a new ice age, this temperature change is unprecedented - and even then , it's the wrong way round.

However, the AGW case rests solidly on the fact that the planet is not disposing of the extra greenhouse gases we're adding to the atmosphere, and the effect of greenhouse gases is to raise atmospheric temperatures.

taconnol wrote: »

The history of the earth is a lot lonver than 10,000. We need to go back much further than 10,000 years.

Yes, I can see what you're saying there. However, pollen records from sediments go back well before 10,000 years, even in Ireland (pollen records include the pre-bog sediments, and in places include fen sediments that are pre-glacial, as far as I remember), as do glacial varve records from around the world. It's true that as we go really far back, we have fewer and fewer records (although the general geological record gives a macro picture of regional climate throughout), so the far reaches are very low-res, but we're certainly not restricted to the last 10,000 years for annual discrimination.

taconnol wrote: »

Also, have you fond a good explanation for the temperature increase from around 1915 to 1940 for which there is no corresponding increase in C02 output? There is a strong correlation between the temperature increase and the increase in C02 output from 1950 to present but I have not heard a good one for the 1915-1940.

I'll have a look for you (sources will be cited!).

taconnol wrote: »

Hmm so you're saying there have been very rapid climate changes in the past, documented? And not caused by humans? Sorry I've only just started studying this so am not aware of all relevant info

Yes, the current view is that climate doesn't vary continuously (as is assumed in the IPCC models for example), but has a series of meta-stable 'settings', and jumps from one to another quite quickly.

cordially,
Scofflaw

Scofflaw

Regarding the 1915-1940 rise. This is from Wikipedia:



The model shows the rise - not exact, and there's almost certainly something else happening, but whatever it is would be a minor effect.

cordially,
Scofflaw

Capt'n Midnight

Better picture

Macha

Scofflaw wrote: »

Regarding the 1915-1940 rise. This is from Wikipedia:



The model shows the rise - not exact, and there's almost certainly something else happening, but whatever it is would be a minor effect.

What else would that something be? Would you have any idea on the % say of global warming caused by human activity?

Really where I think I'm heading is that we have to hedge our bets. We can't spend all of our time and resources on fighting global warming if there is the possibility that this time and resources has little effect. We have to reduce carbon emissions but also start to prepare. What's your take on this?

Scofflaw

taconnol wrote: »

What else would that something be? Would you have any idea on the % say of global warming caused by human activity?

It need not be anything - a cumulative modelling inaccuracy, rather than a missing input. My own guess would be that the effects of volcanic plumes is rather variable.

The amount of anthropogenic input you can actually determine from the graph. We're responsible for the greenhouse gases line, so we're currently putting in about 70% of the climate forcing.

taconnol wrote: »

Really where I think I'm heading is that we have to hedge our bets. We can't spend all of our time and resources on fighting global warming if there is the possibility that this time and resources has little effect. We have to reduce carbon emissions but also start to prepare. What's your take on this?

Well, the original target in CO2e (CO2 equivalent) levels was to stabilise levels below 450ppm, and the original assumption was that climate would respond smoothly, and not very sensitively, to the CO2e rise, without unexpected large positive feedbacks - which would yield an approximate 2°C temperature increase and a roughly 50cm sea level rise purely as a result of thermal expansion of the oceans.

Unfortunately, the latest research suggests that (a) we're already over 450ppm, (b) the climate looks like it will jump to another position rather than rising smoothly, and (c) some large feedbacks are already coming into play, with the Greenland ice cap looking unstable. The Northwest Passage wasn't expected to be ice-free until 2050, but it happened this summer, so things are moving rather more rapidly than envisaged. If Greenland goes, we get a 5m sea level rise by the end of the century, and further warming as a result of the loss of reflective ice.

Even the 'official' skeptics are not denying that climate change is actually happening, although that was the position up to a couple of years ago.

So planning for the effects is a little complicated. My own feeling would be that if there's anything we can do in the way of reducing the forcing - such as lowering greenhouse gas emissions - then we have to do it, because if they are part of the problem, we really need to stop adding to it.

There seems to be a strange assumption that the climate will 'change', and that will be that, we'll have a new steady climate - different, and there'll be adjustments, but we'll adapt. That is not the case. What we have probably done is destabilised the climate, pushing it off the post-glacial steady state we humans have enjoyed for the last 10,000 years, and into a series of swings and jumps - like the moment a tap stops pouring steadily and starts splashing and twisting. And we can keep pushing it, if we're part of the problem and don't do anything about it. We might push the climate to a new stable state, but it's far more likely that we'll just make it jump about more wildly. And planning for that would be a nightmare.

Overall, though, yes we need to start looking at things like disease control for Europe (malaria in particular, but things like bluetongue and West Nile as well - semi-tropical diseases), a complete moratorium on floodplain and low-coastal development, possible rerouting of coastal railways and motorways. In a sense Ireland is doubly lucky - we're not expected to be too heavily affected (under the conservative scenarios), and we don't have a huge amount of infrastructure anyway.

Personally, I don't buy into the 'collapse of civilisation' panic - it's often a cover for people who prefer socialist systems. The Western world can survive by being rather more brutal to the rest of the planet than it has been for the last 50 years - a reversion to early Victorian treatment of poor countries rather than our current enlightened attempts to pull the out of poverty. Militarily, the WW2 powers remain the most heavily armed, so the jackboot rather than the helping hand remains an option. I'm not advocating this, you understand, just pointing out that it is one of the options - albeit an option that involves quite a lot of war.

Globally, about 2 billion people can afford to live as the West does. One option is for about a billion people to decide that they're going to do so, and the rest of the world isn't.

cordially,
Scofflaw

Lennoxschips

Yeah, there's no way we're going to level off at 450 ppm - or even 500 or 600 ppm in my opinion. The "natural" level was about 280/290 ppm, we're already at 380-390 ppm and global CO2 output is not being reduced at all, it's increasing every year. As well as this, the natural CO2 absorption systems are beginning to come under pressure. Oceans are becoming oversaturated and rainforests are being cleared, meaning that CO2 buildup in the atmosphere will increase even faster.

The Greenland ice sheet isn't going to go this century, but the wheels have been set in motion and it will go in the coming millennium. Obviously we'll be dead by then, but our ancestors will be mighty pissed off at us.

The only thing that can curb emissions now is peak oil, because the politicians have no interest in global warming beyond guff-speak.

Capt'n Midnight

Most of the the "developed" world lives in the temperate regions. These aren't climatically stable over the long term. Overthe last few ten of thousands of years England has had Lions and Hippos and a kilometer of ice. The Sahara still has crocodiles from the last wet period. Hungary was a fresh water sea and all the boglands in the midlands were part of a giant lake.

So long term it's going to be difficult to keep the status quo. One could ask would a colder climate with wetter areas where there are deserts be better for hummanity or should we try to get back to several million years ago when South America was joined to Antartica and what is now the circumpolar current instead flowed through the Carribeen and so the climate all over the world was more temperate.

There are other big schemes we are capable of to change the climate. The ob could be diverted southwards to feed the Caspian and Aral seas. This would leave less fresh water in the Artic which would then be saltier and hasten the movement of the Gulf Stream northwards past us. Then again if the Artic is going to be ice free this would happen anyway. An ice free Artic means shipping to Japan is going to be a lot faster and cheaper. Also means that a rail link via Sakhalin may be put on the shelf. Or maybe it would make the Bering Strait Bridge would be easier to build.

For the countries of the Med and Black sea and Baltic sea level rise is a problem because they aren't used to tides and coastal areas are very low. But it's possible to dam off those areas. In the Med you could setup turbines as evaporation means water flow would be inwards. In the Baltic water would have to be pumped out. It could become a giant freshwater lake. Icing would be a problem, unless we get serious warming.

sunny2004

not sure if this is an issue, but just returned from early lunch on a cloudy november day (today) with my partner, she had a short skirt on and I had only a shirt on....

Ahhhhhhhhh I can see the jokes.. I had trousers and she also had a top lol


the point is it is warm..