"weather not the same as climate" ...
You hear this a lot in discussions of climate change. Usually, it's climate change believers talking to skeptics who have used a weather example as an indication that climate change is not real.
That's not my position nor is it entirely valid. Climate at any point in time is the integrated totality of weather events over a defined period. The 30-year normal is something that developed in climatology before it was known as climate science, in the early 20th century (perhaps earlier, I know for sure it was used between the world wars in discussions of climate variability).
What is climate? It's a blend of averages and extremes observed at a location. For example, I just finished a comprehensive study of 180 years of weather records at Toronto. In the 1870s, somebody might have written "the local climate consists of a long, cold and snowy winter, with an average of 100" of snow, and a short but relatively hot and humid summer with frequent heavy rainfalls. " They would have been essentially correct but that would not read very well since about 1920, at the present time, this would be more accurate ... "the local climate consists of a four-month winter season with mixed intervals of cold and mild, a wide variety of precipitation, and long warm to hot summers that alternate between hot and humid, and dry and pleasantly warm, with a few other types sprinked in."
So there has been climate change at Toronto to make these two statements equally accurate.
But even so, that didn't prevent anomalies like an April 1975 blizzard being worse than any recorded April snowfall since 1840, or a 1969 October snowfall coming earlier (10 cm+) than in any previous year. Feb 2015 was so cold that it beat all Februaries since 1840 except 1875 and 1885. And that's the kind of "weather" that climate change people don't want to hear about, but in fact what something like that does, is to change the running average, who knows whether there might be another really cold one in 2025 so that (2015,2025) looks like (1875,1885) to some future observer or analyst.
But in any case, my objection to this news release is that it doesn't really report the facts in context of financial and human-target human-caused (non-atmospheric) factors. When those factors are understood, the meaning of the "finding" changes from alarming to perhaps pedestrian.
Let's get back to the paradigm about weather and climate. They are not two different things. Climate can only be the integrated summary of averages and extremes of weather. Therefore it is always changing. Every day changes the climate incrementally. If you think climate is "normally the weather we get here" then what is that in a high variability climate zone like most of the U.S.A. has, the whole point of U.S. weather is that frequent large variations can be expected. Very few months come out very close to recent averages, and almost equal numbers of them are warmer or colder, wetter or drier.
I follow U.S. weather closely and really, 2020 was a rather bland sort of year compared to many. Considering there were a record number of named storms, the actual landfalls did not add up to all that much compared to some other seasons -- there was no single extreme landfall event like 2018 (Michael in Mexico Beach FL) or 1992 (Andrew) or 1989 (hugo) etc.
These derecho damage tolls are inflated, people make insurance claims on thousand dollar deductible policies and try to run them up so as not to lose a thousand bucks. And if a derecho goes through a number of towns and damages thousands of houses slightly, there's a lot of claims, but it doesn't really add up to much in economic impact. Half the companies weasel out of paying anything anyway. The homeowners have to fix their houses, so money changes hands between them and construction companies. Then there are ongoing droughts -- whose fault is it that people try to farm or ranch in land that has, for centuries, been arid and nearly useless for such purposes? There may have been a few better decades in the late 19th century and early 20th to lure people into such activities, but I'm a frequent visitor to archaeological sites in the southwest, and the native people who settled there faced the same problems in cycles, there was a whole culture in that region (Anasazi) that was wiped out around 1150-1200 AD, either by climate change (drought) or hostile invasion of other native tribes who didn't practice the same horticulture. We will never know for sure what caused them to disappear but we do know that there were many dry years after centuries of relatively favorable conditions. Those people may have migrated far to the north and reinvented themselves in the interior northwest, or they may have died out entirely. They left no written records so it's hard to trace them.
There were weather events in the past that I know would create a firestorm of angst and concern in some circles if they happened nowadays. I would list these few examples:
1900 -- A cat-4 hurricane made a direct hit on Galveston TX, wiped it out and killed 12,000 people. The city had to be rebuilt.
1925 -- F4/5 tornado destruction through IL-IN-OH killed 750 people (March 18th) and wiped out several large towns (Carbondale IL).
1926/28 -- Two major hurricanes struck south FL, if they happened today, damage tolls would be astronomical. Their death tolls would likely be lower due to better warnings, but still considerable.
1929 -- Huge floods on the Ohio and Mississippi rivers were far greater than anything seen since that event, the economic impact was huge (probably about a ten billion dollar event in today's economy).
1933-37 -- Devastating heat waves and drought hit large areas of the central and eastern U.S., temperatures hit levels not seen since, in some cases by 5 C or 9 F deg (NYC 106 F, Toronto 105 F, Steele ND over 120 F -- nowadays 105-110 is considered extreme there, and at Toronto, ten of eleven days that have exceeded 100 F were before 1953, only one in 2011 since then.
1938 -- The Long Island hurricane, probably a 2-3 billion dollar impact in today's economy.
1954-55 -- Two very active hurricane seasons with some high impact flooding events, Hazel (1954) reached Toronto as a tropical storm and wiped out rows of houses in a floodplain no longer inhabited, killing 80 people. Nothing like that has happened since.
Those are just a few examples of high impact weather events from the so-called "normal" climate that the so-called "extreme" climate has replaced. This is why a lot of people are skeptical, because they don't recall all that many similar high impact events in more recent years.
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