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CC3 -- Why I believe that a third option is needed for climate change
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But your table doesn't show thisUsing French records of highest recorded, if you remove 2019 as weather anomaly and not indicative of a climate pattern change, +40c has been recorded in each decade from 1900.
2019 certainly seems like an anomaly, this is not to say that average temperatures in France are not on the rise, but a previous comment about exceptionally hot summers in Europe being unheard or is not what the data suggests.
Taken from Wiki.
There was no 40+ years in the 1910s,1930s, 1950s, or 1970s, the frequency of such heatwaves was closer to once every 20 years, and the heatwaves were not widespread or long lasting
In fact, it shows that over the past 119 years, there have been 14 years when temperatures exceeded 40c and 5 of those occured in the past 20 years
20 is 16% of 120, so in 16% of the years, there were 35% of the years surpassing 40c
Here's a graph of those data showing how often per decade this 40c barrier was breached,In the 2010s 3 years broke that record, I suggest that the 2020s will likely see at least 50% of years record temp
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The most recent studies have found a satistically significant increasing trend in the number of major storms over the past 4 decades, now, you might not think 4 decades is long enough to come to a conclusion, but we're stuck with the data that we have, previous records are too heterogenious to properly compare using observed records.
If you look at cyclone activity globally rather than focusing on individual regions where there may be more natural cycles in play, you can smooth out these cycles to get a better overall view on how climate change is affecting global tropical cyclone activity.
You can hypothesise that in the 1700s there were more powerful storms but there will always be once in a century storms, often even several of those storms in the same century due to the way probabilty works. The problem is that climate change models predict that there may be fewer hurricanes overall, but that there will be more major hurricanes, and that those hurricanes will cause increased flooding due to warmer oceans feeding them and warmer air allowing them to hold more moisture
We have model based predictions, and we can compare those predictions to the actual outcomes that we are observing, and the evidence is mounting that there is a statistically significant rise in the number of severe storms globally
I've posted a study below, the conclusions of the researchers are that there was a recent decadal increase of 8% in the number of major storms globally
Every year that passes will give us more data to add to the statistical significance of these trends but we cannot wait until there is absolutely no uncertainty because 1. that will never happen, and 2, by that time it will be much too late to delay or reverse the worst impacts of climate change
But in a warming world, where global ocean heat content is supposed to be increasing, why are we seeing no statistically significant increase in global ACE? Regional variability aside, the overall global trend should be increasing. A higher number of stronger, more powerful and longer-lasting storms should show a much more significant trend than just 0.4 (about 0.05%) per annum, given that ACE is related to max wind squared. Where's all that extra energy gone?
http://tropical.atmos.colostate.edu/Realtime/index.php?arch&loc=global
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Gaoth Laidir wrote: »But in a warming world, where global ocean heat content is supposed to be increasing, why are we seeing no statistically significant increase in global ACE? Regional variability aside, the overall global trend should be increasing. A higher number of stronger, more powerful and longer-lasting storms should show a much more significant trend than just 0.4 (about 0.05%) per annum, given that ACE is related to max wind squared. Where's all that extra energy gone?
http://tropical.atmos.colostate.edu/Realtime/index.php?arch&loc=global
ACE is a crude measurement that only looks at wind speed and duration. It doesn’t account for the size of the storm. There is evidence that storms are getting bigger and more destructive
A Cat 5 hurricane like IRMA with a diameter of about 640km was bigger than most Cat5 hurricanes but only half the diameter of Sandy (1400km)
Sandy had a much lower ACE (I can’t even find it easily because it’s so unremarkable)
That One of the most destructive storms on record barely ranked on the ACE rating system shows that it is clearly missing some important parameters
The study I linked to used satellite photos to include the size of all global tropical cyclones in their calculations. There are also multiple other studies that measure the destructiveness of storms using different methodologies that conclude that storms have been getting worse as the planet warms0 -
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ACE is a crude measurement that only looks at wind speed and duration. It doesn’t account for the size of the storm. There is evidence that storms are getting bigger and more destructive
A Cat 5 hurricane like IRMA with a diameter of about 640km was bigger than most Cat5 hurricanes but only half the diameter of Sandy (1400km)
Sandy had a much lower ACE (I can’t even find it easily because it’s so unremarkable)
That One of the most destructive storms on record barely ranked on the ACE rating system shows that it is clearly missing some important parameters
The study I linked to used satellite photos to include the size of all global tropical cyclones in their calculations. There are also multiple other studies that measure the destructiveness of storms using different methodologies that conclude that storms have been getting worse as the planet warms
The theory stated in the article you posted relates storm intensity to a warming world. So what do they mean by intensity? Have the goalposts now shifted and intensity no longer refers to max winds and minimum pressure and storm longevity (something you're quick to quote when these numbers become interesting, e.g. in the case of Patricia)? It's now moved on to not so much how hard she blows but rather where she blows? The real estate of the landfall point is now a factor? Had Sandy not made landfall where it did we would not be talking about it. It briefly reached Cat 3 earlier on and was barely a Cat 1 when it did hit, so all the damage was done by the storm surge. As MT has shown, this is not the first time this area has been hit by such storms, but when you put 100 million people (more importantly, Americans) in the way then everything stops and the media frenzy starts.
The actual number of Atlantic Cat 3+ storms in the past 40 years shows a meagre rise of around 0.5 storms per decade, or an increase of just +1.5 storm days per decade. This is in the most sensitive basin in the world. In the NW Pacific the trend is even less pronounced (+0.2 storms and +0.8 days per decade), despite a rise of around 0.7 °C in 0-100 m water heat content there. Yet we are to believe that there are clear and unequivocal signs of destructive increases in this basin, home to hundreds of millions of vulnerable populations, but the data don't reflect this.
Storm size is one thing, but even that study said that it couldn't find a trend in a 28-year dataset and had to extend out to 39 years (cherrypicking, as you say?) to find one. This is exactly of the same magnitude of the natural variability of the system (AMO, etc.), to which the Atlantic storm activity and that of other basins are primarily linked.
ACE is one of the prime measurements used by the NHC and other bodies in classifying individual storms and seasons. Just because it is not showing any appreciable trend is not a reason to discard it. If indivicual storms really are becoming stronger then ACE should be showing it. Size doesn't matter.0 -
Gaoth Laidir wrote: »The theory stated in the article you posted relates storm intensity to a warming world. So what do they mean by intensity? Have the goalposts now shifted and intensity no longer refers to max winds and minimum pressure and storm longevity (something you're quick to quote when these numbers become interesting, e.g. in the case of Patricia)? It's now moved on to not so much how hard she blows but rather where she blows? The real estate of the landfall point is now a factor? Had Sandy not made landfall where it did we would not be talking about it. It briefly reached Cat 3 earlier on and was barely a Cat 1 when it did hit, so all the damage was done by the storm surge. As MT has shown, this is not the first time this area has been hit by such storms, but when you put 100 million people (more importantly, Americans) in the way then everything stops and the media frenzy starts.
The actual number of Atlantic Cat 3+ storms in the past 40 years shows a meagre rise of around 0.5 storms per decade, or an increase of just +1.5 storm days per decade. This is in the most sensitive basin in the world. In the NW Pacific the trend is even less pronounced (+0.2 storms and +0.8 days per decade), despite a rise of around 0.7 °C in 0-100 m water heat content there. Yet we are to believe that there are clear and unequivocal signs of destructive increases in this basin, home to hundreds of millions of vulnerable populations, but the data don't reflect this.
Storm size is one thing, but even that study said that it couldn't find a trend in a 28-year dataset and had to extend out to 39 years (cherrypicking, as you say?) to find one. This is exactly of the same magnitude of the natural variability of the system (AMO, etc.), to which the Atlantic storm activity and that of other basins are primarily linked.
ACE is one of the prime measurements used by the NHC and other bodies in classifying individual storms and seasons. Just because it is not showing any appreciable trend is not a reason to discard it. If indivicual storms really are becoming stronger then ACE should be showing it. Size doesn't matter.
The study did find a trend in the original 28 year dataset, but the dataset was too small to give it statistical significance at the 95% confidence interval. Extending the dataset didn't change the trend they found earlier, it gave them enough data to say that it is a signal and not just noise.
Size absolutely does matter when it comes to the destructive power of storms. the size of the windfield affects the storm surge and the larger the wind field the more energy there is in the storm system, the longer that storm will affect each place it hits, while hitting more places the size can affect how much wind and rain damage it can cause as it can take longer for the storm to overpass or dissapate
ACE only measures 2 things, peak wind speed, and duration
It has its uses because it can be extended back further in time to before we had good satelilite measurements to record the size and pressure of the storm system, and because the calculations are much easier to make
There is a better more comprehensive measurement called Integrated Kinetic Energy (IKE) which takes the ACE measurements and expands on it with zonal wind speed calculations it can also calculate the storm surge potentia for each storm as it reaches landfall
https://www.aoml.noaa.gov/hrd/ike/Calculator_AllQuad.php
But it is limited to the power of a storm at landfall rather than the power of all storms in a basin, or globally over a season
Track Integrated Kinetic Energy builds further on that system to include the storm along it's whole track from when it becomes a tropical cycone rather than just at the point it makes landfall but there don't seem to be enough scientists working on building the data to properly analyse historical annual or decadal trends using these metrics0 -
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