I wish such articles would not always compare with averages. It is perfectly normal if sometimes measurements are above averages and sometimes below. At the very least, they should also give a range.
Not saying there is no cause for concern, but saying "this year was above average" is meaningless in itself.
As for the July record, OK - but also some points in time have to be the record.
Are years the appropriate units for such comparisons, though?
Anyway I give them their record, my main gripe is really the talk about averages. It's just plain misleading or at least not as informative as it could be.
Decades are a better unit, but new decades only come once every 10 years. Units less than a year are problematic because of seasons. For example, you could say that July was the hottest month on record this year, and that wouldn't really tell you anything interesting (except that maybe more humans live in the north hemisphere and we mostly take observations where humans live).
> For example, you could say that July was the hottest month on record this year, and that wouldn't really tell you anything interesting (except that maybe more humans live in the north hemisphere and we mostly take observations where humans live).
Water has a relatively large heat capacitance, which means that it is more resistant to changing temperature. As a result, places near large bodies of water tend to see lower highs and higher lows than places not near them. Compare the climate of, say, Mumbai (whose highs vary between 30 and 34C around the year) versus Nagpur (whose highs vary between 29 and 43C), both of which are at roughly the same latitude, but one is coastal and the other substantially more inland.
The southern hemisphere has very little land, especially in the temperate belt (between Tropic of Capricorn and Antarctic Circle)--that land is Argentina, Chile, Uruguay, a smallish part of Brazil, South Africa, half of Australia, New Zealand, and small fragments of a few more countries. There's no major landmasses to vary in temperature with the seasons like there is in the northern hemisphere, and hence the southern hemisphere has a much smaller role than the northern hemisphere in measuring global climatic fluctuations.
A better comparison would be to say "the hottest 10 days were all this July. There seems to be a trend here". Then it would be obvious that it was simply the hottest July, so of course all days were comparatively hot.
Just saying that there could be climate patterns that span more than a year, and "all the hottest Julies where in the last ten years" would be similar to saying "all the hottest days were in the last month".
Not saying it is the case, but also not saying that I automatically believe the fearmongering.
> As for the July record, OK - but also some points in time have to be the record.
Yes, if you have a sequence of comparable values that are not all identical, one of those values is the maximum.
If you keep hitting maxima at a rate that's not decreasing, then the sequence is trending upward. In this case not only is the rate of record-breaking not decreasing, it's increasing.
For me in South Texas, it was one of the coolest summers I can remember. We had no days at or above 100, and most of the month was below average.
This was due to the High Pressure dome not being over us as it normally is, causing us to have lots of rain.
Many Texans were happy that this summer wasn't a scorcher. While I understand that this weather isn't good (or normal) for us, I fear the nice weather will just make more Texans not care about climate change.
We've been "enjoying" your high pressure system up in the Pacific Northwest. There are plenty of places at the equator that were cooler than Vancouver yesterday. You can have it back. Please.
I was looking at the glacier above Joffre lakes (north of Whistler) on Wednesday and thinking that it will probably be gone in my lifetime. It looks smaller this year than the last time I was there four or five years ago. I looked for photos of it this time of year in the past, but my Google fu failed.
For me in Rhode Island, it's been quite warm. Today @ 91 degrees is similar to trend I've seen all summer - a near uniform temperature for the whole East Coast. It's 91 today in Atlanta GA, Jackson MS, & Houston TX.
It's also 91 in Burlington VT & Bangor ME. It's been strange like that all summer.
It's 85°F in my backyard right now, I can remember several summers where the night time low in mid-August stayed above 85 (or 90). Those are miserable days.
I've been happy at how relatively cool it's been. I don't think I've seen a single day in triple digits yet and it's the first time I can remember that happening since moving to Texas. Not a fan of the rain, though, but I guess it's probably good for the land.
It's definitely been weird sitting here in the coolest summer I can remember hearing about these heat records being set elsewhere, but thankfully I well understand how averages and spatial variation work.
Instead of "warmest", we need to use "hottest" or "highest temperature". Warm sounds like it is nice and cozy. I live in Seatte and it was NOT nice and cozy.
A weather station in Sicily, Italy recorded 120 degrees celsius heat at one point. 120 degrees celsius. 20 degrees higher than boiling point of water...
That was 120 degrees Farenheit, not Celsius. 120 degrees Celcius is 248 degrees Farenheit, which is obviously not a surface temperature on earth (at least not yet).
Bottom line: records are extremely rare if events occur at random. If new records become far more common than the harmonic series predicts, then this is telling us that annual climatic events are no longer independent annual events but are beginning to form part of a systematic non-random trend.
Not according to the Earth System Science Center in University of Alabama-Huntsville. July 2021 was only 0.2C above the 1991-2020 average based on satellite measurements of the lower troposphere.
Ground temperature measures air temperate at 1.5 meters. Lower troposphere measures the average from 0 meters to 10 km, weighted heavily toward the lower 4 km.
It's not exactly intuitive why ground temperature and lower troposphere temperature should be different, but in short, during wet seasons, troposphere will be relatively warmer, and during dry seasons, ground will be relatively warmer. I think ground is what we care about here, though, as that most directly impacts human wellbeing.
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[ 4.0 ms ] story [ 89.4 ms ] threadhttps://www.carbonbrief.org/guest-post-deciphering-the-rise-...
This is an understatement of century.
It would be better to say that the speed at which the ice cover melts exceeded worst case projections of even most pessimistic scientists.
Not saying there is no cause for concern, but saying "this year was above average" is meaningless in itself.
As for the July record, OK - but also some points in time have to be the record.
> The seven warmest Julys have all occurred since 2015.
There seems to be a trend there.
Anyway I give them their record, my main gripe is really the talk about averages. It's just plain misleading or at least not as informative as it could be.
Water has a relatively large heat capacitance, which means that it is more resistant to changing temperature. As a result, places near large bodies of water tend to see lower highs and higher lows than places not near them. Compare the climate of, say, Mumbai (whose highs vary between 30 and 34C around the year) versus Nagpur (whose highs vary between 29 and 43C), both of which are at roughly the same latitude, but one is coastal and the other substantially more inland.
The southern hemisphere has very little land, especially in the temperate belt (between Tropic of Capricorn and Antarctic Circle)--that land is Argentina, Chile, Uruguay, a smallish part of Brazil, South Africa, half of Australia, New Zealand, and small fragments of a few more countries. There's no major landmasses to vary in temperature with the seasons like there is in the northern hemisphere, and hence the southern hemisphere has a much smaller role than the northern hemisphere in measuring global climatic fluctuations.
Just saying that there could be climate patterns that span more than a year, and "all the hottest Julies where in the last ten years" would be similar to saying "all the hottest days were in the last month".
Not saying it is the case, but also not saying that I automatically believe the fearmongering.
Yes, if you have a sequence of comparable values that are not all identical, one of those values is the maximum.
If you keep hitting maxima at a rate that's not decreasing, then the sequence is trending upward. In this case not only is the rate of record-breaking not decreasing, it's increasing.
In any case, I give them their record. My main issue was with the comparison to averages.
Often they even call it "anomaly" which may technically be correct, but sounds much more scary than necessary.
This was due to the High Pressure dome not being over us as it normally is, causing us to have lots of rain.
Many Texans were happy that this summer wasn't a scorcher. While I understand that this weather isn't good (or normal) for us, I fear the nice weather will just make more Texans not care about climate change.
https://www.bloomberg.com/opinion/articles/2021-08-12/u-s-cl...
It's also 91 in Burlington VT & Bangor ME. It's been strange like that all summer.
It's definitely been weird sitting here in the coolest summer I can remember hearing about these heat records being set elsewhere, but thankfully I well understand how averages and spatial variation work.
https://books.google.com/books?id=N0FLSOmeFPsC&pg=PT59
Bottom line: records are extremely rare if events occur at random. If new records become far more common than the harmonic series predicts, then this is telling us that annual climatic events are no longer independent annual events but are beginning to form part of a systematic non-random trend.
Not according to the Earth System Science Center in University of Alabama-Huntsville. July 2021 was only 0.2C above the 1991-2020 average based on satellite measurements of the lower troposphere.
Greenland had a mild melt season and is currently above 1981-2010 average surface mass balance: http://polarportal.dk/en/greenland/surface-conditions/
The southern hemisphere has had a rather cold winter, resulting in below average temps for South America, South Africa and Australia.
Brazil had snow: https://www.smithsonianmag.com/smart-news/rare-snowfall-blan...
Coffee crops froze in July. https://www.reuters.com/world/americas/freak-brazil-frost-hi...
Four south african cities had their coldest temps on record: https://www.thesouthafrican.com/news/weather/breaking-weathe...
Australia had one of its coldest, wettest July's in decades: https://www.news.com.au/technology/environment/wettest-july-...
Antarctica sea ice extent is well above 1981-2010 average: https://usicecenter.gov/Products/AntarcCharts
Ground temperature measures air temperate at 1.5 meters. Lower troposphere measures the average from 0 meters to 10 km, weighted heavily toward the lower 4 km.
It's not exactly intuitive why ground temperature and lower troposphere temperature should be different, but in short, during wet seasons, troposphere will be relatively warmer, and during dry seasons, ground will be relatively warmer. I think ground is what we care about here, though, as that most directly impacts human wellbeing.