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Tor Bejnar

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Re: Heatwaves
« Reply #400 on: December 18, 2019, 02:50:43 PM »
Think:  the average [edit: maximum]for the Australian continent (OK, including 'cool' Tasmania [ave ~20-21C]) was 40.9ºC (105.6ºF).  Large swaths of central and southern Australia (per map at the linked article) had averages over 45ºC.


[Thanx for correction.]
« Last Edit: December 19, 2019, 09:07:29 PM by Tor Bejnar »
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

nanning

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Re: Heatwaves
« Reply #401 on: December 18, 2019, 06:12:11 PM »
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

Tom_Mazanec

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Re: Heatwaves
« Reply #402 on: December 18, 2019, 06:25:28 PM »
Think:  the average for the Australian continent (OK, including 'cool' Tasmania [ave ~20-21C]) was 40.9ºC (105.6ºF).  Large swaths of central and southern Australia (per map at the linked article) had averages over 45ºC

What is the lethal limit again (I believe those areas are dry, BTW)?

KiwiGriff

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Re: Heatwaves
« Reply #403 on: December 18, 2019, 06:28:28 PM »
Question.
Is this linked to the -sudden-stratospheric-warming event as it seems to confirm the predictions of future weather?
Here in NZ we have also had a series of stormy fronts hitting the south island as predicted.
https://www.sciencealert.com/antarctica-s-sudden-stratospheric-warming-is-impacting-australia
Quote
For regions directly in the path of the strongest westerlies, which includes western Tasmania, New Zealand's South Island, and Patagonia in South America, this generally results in more storminess and rainfall, and colder temperatures.

But for subtropical Australia, which largely sits north of the main belt of westerlies, the shift results in reduced rainfall, clearer skies, and warmer temperatures.

Past stratospheric warming events and associated wind changes have had their strongest effects in NSW and southern Queensland, where springtime temperatures increased, rainfall decreased and heatwaves and fire risk rose.
Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
Notebooks of Lazarus Long.
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KiwiGriff

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Re: Heatwaves
« Reply #404 on: December 18, 2019, 06:39:06 PM »
The lethal limit is dependent on humidity as well as temperature.
Au the conditions that produce the high temps are very dry winds from the interior.

A wet bulb temperature over 35C  is  lethal.
https://www.omnicalculator.com/physics/wet-bulb
For 50C to be lethal you need about 35% humidity.
Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
Notebooks of Lazarus Long.
Robert Heinlein.

gerontocrat

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Re: Heatwaves
« Reply #405 on: December 18, 2019, 07:38:05 PM »
The lethal limit is dependent on humidity as well as temperature.
Au the conditions that produce the high temps are very dry winds from the interior.

A wet bulb temperature over 35C  is  lethal.
https://www.omnicalculator.com/physics/wet-bulb
For 50C to be lethal you need about 35% humidity.
As long as you keep in the shade. In Malawi, a long time ago, a big noise from the EU came to our project. He was a most objectionable man, demanded a safari - as in "Sanders of the River" colonial times. He also demanded an open-topped Landrover.  So off he went, in 40+ degrees heat, without a hat. And he was bald.

We were not minded to advise him of the likely consequence. He was not a well man when he came back somewhat sooner than planned.

Shame.
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KiwiGriff

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Re: Heatwaves
« Reply #406 on: December 18, 2019, 07:56:29 PM »
We get the same effect here. We know better than you ignorant colonials.
I always warn visiting relatives to watch out for NZ's UV levels, Pasty white pommy's will burn in half an hour even on a cloudy day in NZ's summer.
They never listen and end up crispy crittered.
Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
Notebooks of Lazarus Long.
Robert Heinlein.

vox_mundi

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Re: Heatwaves
« Reply #407 on: December 18, 2019, 08:15:00 PM »
Quote
... So off he went, in 40+ degrees heat, without a hat. And he was bald.

We were not minded to advise him of the likely consequence. He was not a well man when he came back somewhat sooner than planned.

“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

Rodius

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Re: Heatwaves
« Reply #408 on: December 19, 2019, 01:06:58 AM »
Question.
Is this linked to the -sudden-stratospheric-warming event as it seems to confirm the predictions of future weather?
Here in NZ we have also had a series of stormy fronts hitting the south island as predicted.
https://www.sciencealert.com/antarctica-s-sudden-stratospheric-warming-is-impacting-australia
Quote
For regions directly in the path of the strongest westerlies, which includes western Tasmania, New Zealand's South Island, and Patagonia in South America, this generally results in more storminess and rainfall, and colder temperatures.

But for subtropical Australia, which largely sits north of the main belt of westerlies, the shift results in reduced rainfall, clearer skies, and warmer temperatures.

Past stratospheric warming events and associated wind changes have had their strongest effects in NSW and southern Queensland, where springtime temperatures increased, rainfall decreased and heatwaves and fire risk rose.

The sudden-stratospheric-warming event earlier this year is linked to more extreme dryness and heat in Australia and to the storms in NZ.
There are articles posted in the Antarctica part of the forum. This effects should only last another 1 to 3 months.

iamlsd

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Re: Heatwaves
« Reply #409 on: December 19, 2019, 02:40:46 AM »
If I'm reading this correctly then Cape Borda in South Australia is currently above 35 C wet bulb temp and lethal.  :-[
http://www.bom.gov.au/products/IDS60801/IDS60801.95805.shtml

Date/TimeCDT Temp°C    AppTemp°C  DewPoint°C   RelHum%
19/12:00pm      38.6       53.6             38.6               100     
19/11:30am      37.9       51.4             37.8               99
19/11:00am      36.1       47.3             36.1               100
19/10:30am      34.9       44.5             34.6               98
*Note I expect this is a data error of some sort and sent feedback to BOM asking them to check. Temps above 44C today and over 40C Tuesday to Friday this week where I am in Adelaide are extreme enough.  :o
« Last Edit: December 19, 2019, 05:23:41 AM by iamlsd »

nanning

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Re: Heatwaves
« Reply #410 on: December 19, 2019, 06:26:12 AM »
Those relative humidity figures seem way off.
Something strange is forecasted for 10AM.

I found this:
http://www.bom.gov.au/products/IDS60801/IDS60801.95805.shtml
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

Rodius

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Re: Heatwaves
« Reply #411 on: December 19, 2019, 08:21:48 AM »
Australia has experienced its hottest day on record with the national average temperature reaching a high of 40.9C (105.6F).

...

Forecasters had predicted the most intense heat would come later in the week, meaning the record could be broken again.

https://www.bbc.com/news/world-australia-50817963


That recorded lasted only 24 hours and is now 41.9.
I might be wrong in thinking this, but an entire degree upwards seems significant and very large.

What is genuinely concerning is tomorrow is going to be hotter.
What is even more bothersome is December isnt the hottest month and this is happening.


https://www.news.com.au/technology/environment/australia-records-hottest-day-ever-for-second-day-running/news-story/b785458fe1a07b718f57db408212712b

Tom_Mazanec

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Re: Heatwaves
« Reply #412 on: December 19, 2019, 11:14:18 AM »
Rodius:
I remember when, in the summer of 1988, we hit 40 C in June, and I worried what July and August would bring. But the were actually below that.

Ktb

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Re: Heatwaves
« Reply #413 on: December 19, 2019, 12:47:47 PM »
Think:  the average for the Australian continent (OK, including 'cool' Tasmania [ave ~20-21C]) was 40.9ºC (105.6ºF).  Large swaths of central and southern Australia (per map at the linked article) had averages over 45ºC

Distinctions must be made -- Average maximum temperature.
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- Ishmael

be cause

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Re: Heatwaves
« Reply #414 on: December 19, 2019, 12:54:22 PM »
glad I'm not an Aussie ..with beard and 'tash these days my experience would be akin to waterboarding ..b.c.
Conflict is the root of all evil , for being blind it does not see whom it attacks . Yet it always attacks the Son Of God , and the Son of God is you .

iamlsd

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Re: Heatwaves
« Reply #415 on: December 19, 2019, 01:42:50 PM »
Minimum tonight in Adelaide is 32C then forecast high tomorrow is 46C. Later in the day a change is coming through and the temps should drop. However while the change comes through there will be strong winds so we also have a catastrophic fire danger warning. Perhaps a few of the climate change sceptics might finally change their minds.  Unfortunately this sort of extreme conditions will get more frequent.  :-[

nanning

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Re: Heatwaves
« Reply #416 on: December 19, 2019, 01:57:26 PM »
Quote from: be cause
with beard and 'tash these days

Could you enlighten me on the meaning of " 'tash "? My creative brain is letting me down. Is it obesity? The more fat, the warmer. Though I don't picture you as a fat man in my mind.

This text on your gravestone will raise some eyebrows: "Drowned in his own sweat" :P
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

kassy

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Re: Heatwaves
« Reply #417 on: December 19, 2019, 02:25:04 PM »
Goes with a beard and is beneath the nose.  ;)
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

nanning

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Re: Heatwaves
« Reply #418 on: December 19, 2019, 02:53:50 PM »
Oops. Thanks kassy.


Done in a Datsun: Man cooks roast pork in car during Australian heatwave
  by Reuters

http://news.trust.org/item/20191217045443-nspw4/
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

Sigmetnow

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Re: Heatwaves
« Reply #419 on: December 19, 2019, 04:58:22 PM »
Wednesday set another record.
Quote
Ryan Maue on Twitter: "Preliminary Australia continental high temperature was 107°F (41.7°C) Wednesday. That's the hottest on record, again. Data from Australia Bureau of Meteorology. I make maps.
https://mobile.twitter.com/ryanmaue/status/1207333203578626048
Image below.
People who say it cannot be done should not interrupt those who are doing it.

Gray-Wolf

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Re: Heatwaves
« Reply #420 on: December 19, 2019, 06:46:48 PM »
Wednesday set another record.
Quote
Ryan Maue on Twitter: "Preliminary Australia continental high temperature was 107°F (41.7°C) Wednesday. That's the hottest on record, again. Data from Australia Bureau of Meteorology. I make maps.
https://mobile.twitter.com/ryanmaue/status/1207333203578626048
Image below.

Ozzy Summer begins this weekend does it not?......
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ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
 
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Tor Bejnar

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Re: Heatwaves
« Reply #421 on: December 19, 2019, 06:51:58 PM »
 " 'tash " = "mustache"
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

Tom_Mazanec

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Re: Heatwaves
« Reply #422 on: December 19, 2019, 06:54:12 PM »
As Dr. Ivo "Eggman" Robotnik said "You got to flash the 'tash".

nanning

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Re: Heatwaves
« Reply #423 on: December 19, 2019, 08:07:50 PM »
Thanks Tor. I already got a nice answer from kassy above. Now I picture you as Old Shatterhand  ;D
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

grixm

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Re: Heatwaves
« Reply #424 on: December 19, 2019, 09:27:21 PM »
Nullarbor weather station seems to have recorded 50C today, is that official?

http://www.ogimet.com/cgi-bin/gsynres?lang=en&ind=94651&ano=2019&mes=12&day=19&hora=18&min=0&ndays=30

Rodius

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Re: Heatwaves
« Reply #425 on: December 20, 2019, 02:04:13 AM »
Rodius:
I remember when, in the summer of 1988, we hit 40 C in June, and I worried what July and August would bring. But the were actually below that.

Which country as that?

Our hot months are Jan and Feb. I suspect the differences to '88 is it is unlikely to let up for another six weeks due to underlying conditions. Given how much has dried out already, the bush fires which are, to put it mildly, fucking huge, and looking to hit Sydney suburbs in the coming weeks, this heatwave is something special.

What is truly amazing is our political "leader" decided to go on holiday to Hawaii for a well-deserved break. He still thinks climate change is a myth, has embarrassed the country at the latest climate forum, it just boggles me how hard it must be to kept ignoring the evidence burning down the doors.

I hope what happened to you happens for us. Want a bet that we will break the record again before the end of Feb 2020? :)

Lewis

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« Last Edit: December 20, 2019, 03:29:59 AM by Lewis »

Juan C. García

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Re: Heatwaves
« Reply #427 on: December 20, 2019, 03:25:25 AM »
Australia National Record:
Quote
Australia has its hottest day for a second straight day as areas face ‘catastrophic’ fire conditions

SYDNEY — Australia is in the throes of one of its most extreme heat events, having broken a national record for the hottest nationally averaged high temperature on two straight days. The Australian Bureau of Meteorology (BOM) reports preliminary data shows that for Dec. 18, the nationally averaged maximum temperature was 107.4 degrees Fahrenheit (41.9 Celsius).

This beat the old record of 105.6 degrees (40.9 Celsius), which had been set just the day before. Before this heat event, the country’s hottest day was Jan. 7, 2013, which had an average high temperature of 104.5 degrees (40.3 Celsius).

“Catastrophic” fire conditions, the most severe category, are forecast Friday in parts of South Australia, as hot weather combines with an expected wind shift that could wreak havoc with firefighting operations.
https://www.washingtonpost.com/weather/2019/12/19/australia-has-its-hottest-day-second-straight-day-areas-face-catastrophic-fire-conditions/?utm_campaign=energy_and_environment&utm_medium=Email&utm_source=Newsletter&wpisrc=nl_green&wpmm=1
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

P-maker

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Re: Heatwaves
« Reply #428 on: December 20, 2019, 08:12:13 AM »
It's amazing!

When I visited Sydney about a decade ago, I came to realize that this place had one of the best climates in the World. No need to heat your house in the winter and no need to cool it in the summer.

Now, it's all about cooling down the air around you, you also need to clean the air to survive, and you have even turned your water reservoirs into ash swamps.

How come, we have transformed one of the best natural climates into some of the worst and harshest living conditions on Earth?

I wonder what some of the worse climates will look like in a few years time.

vox_mundi

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Re: Heatwaves
« Reply #429 on: December 21, 2019, 07:14:45 PM »
Water Thieves Steal 80,000 Gallons in Australia as Our Mad Max-Style Future Becomes Reality
https://earther.gizmodo.com/water-thieves-steal-80-000-gallons-in-australia-as-our-1840549648?utm_medium=socialflow&utm_campaign=socialflow_gizmodo_facebook&utm_source=gizmodo_facebook&fbclid=IwAR1k8Iuo8QY1kI3fT7mLikIAoazXT_lojbuU4gVt4gVyVWIafSn0OGtQQbA

Thieves stole roughly 80,000 gallons of water in a region of Australia that’s suffering from one of the worst droughts in the history of the country. And with record-breaking heat and bushfires getting even larger, it feels like Australia is living in the future. That future, unfortunately, looks a lot like Mad Max.

Police in New South Wales, Australia’s most populous state, report that a farmer in the small town of Evans Plain had about 80,000 gallons of water (300,000 liters) stolen from his property, according to the Australian newspaper. The farmer only noticed the theft from two enormous storage tanks on Sunday, though it could have happened at anytime between December 9 and December 15, according to authorities.

It’s becoming more and more common to see thieves targeting water storage facilities, as climate change continues to devastate Australia as it heads into summer. Just a couple of weeks ago, thieves in the small town of Murwillumbah stole about 6,600 gallons (25,000 liters) of water, enough to fill about six or seven fire trucks, according to local authorities.

And it all feels like something out of a sci-fi dystopia, where battles over water are fought to sustain a meager existence.
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

vox_mundi

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Re: Heatwaves
« Reply #430 on: January 30, 2020, 04:58:01 PM »
New Global Record ‘Likely’ Within Five Years
https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2020/decadal-forecast-2020

The coming five years are anticipated to be warmest period on record, Britain's Met Office said Thursday, warning of an outside chance of Earth breaching the Paris deal 1.5C temperature rise cap before 2024.

In a regular "decadal forecast" looking at predicted near-term climate trends, it said that each year between 2020-2024 is set to be 1.06-1.62C hotter than historical averages.

The Met Office forecast it "likely" that the hottest year on record, 2016, will be beaten in that time frame.

The forecast said that barring a large volcanic eruption that could dent global heating with Sun-blocking debris, average five-year temperatures are expected to be between 1.15-1.46C above pre-industrial levels.

That compares with an average warming in 2015-2019 of 1.09C. All years in that period were among the hottest on record.

The Met Office forecast said there was an outside chance (roughly 10 percent) that a single year between 2020 and 2024 could exceed the 1.5C threshold.
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― anonymous

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

P-maker

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Re: Heatwaves
« Reply #431 on: February 22, 2020, 05:41:03 PM »
A new study on the connections between European heatwaves, Arctic sea ice and NH snow cover has been released:

Quote
Quote
The combined effects of declined ASIC and EASC, accompanied by the drier soil and the stronger heat flux, tend to weaken the poleward temperature gradient at mid–high latitudes and affect the midlatitude jet stream and transient eddy activities. These dynamic and thermodynamic circulations increase the likelihood of more persistent European blocking events that favor frequent and strengthened heat waves."

Further details are available at: https://www.nature.com/articles/s41612-020-0110-8

vox_mundi

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Re: Heatwaves
« Reply #432 on: May 08, 2020, 09:40:29 PM »
Potentially Fatal Combinations of Humidity and Heat Are Emerging Across the Globe
https://phys.org/news/2020-05-potentially-fatal-combinations-humidity-emerging.html

Recently, some scientists have projected that later in the century, in parts of the tropics and subtropics, warming climate could cause combined heat and humidity to reach levels rarely if ever experienced before by humans. Such conditions would ravage economies, and possibly even surpass the physiological limits of human survival.

According to a new study, the projections are wrong: such conditions are already appearing. The study identifies thousands of previously rare or unprecedented bouts of extreme heat and humidity in Asia, Africa, Australia, South America and North America, including in the U.S. Gulf Coast region. Along the Persian Gulf, researchers spotted more than a dozen recent brief outbreaks surpassing the theoretical human survivability limit. The outbreaks have so far been confined to localized areas and lasted just hours, but they are increasing in frequency and intensity, say the authors. The study appears this week in the journal Science Advances.

Analyzing data from weather stations from 1979 to 2017, the authors found that extreme heat/humidity combinations doubled over the study period. Repeated incidents appeared in much of India, Bangladesh and Pakistan; northwestern Australia; and along the coasts of the Red Sea and Mexico's Gulf of California. The highest, potentially fatal, readings, were spotted 14 times in the cities of Dhahran/Damman, Saudi Arabia; Doha, Qatar; and Ras Al Khaimah, United Arab Emirates, which have combined populations of over 3 million. Parts of southeast Asia, southern China, subtropical Africa and the Caribbean were also hit.

The southeastern United States saw extreme conditions dozens of times, mainly near the Gulf Coast in east Texas, Louisiana, Mississippi, Alabama and the Florida Panhandle. The worst spots: New Orleans and Biloxi, Miss. Such conditions also reached inland into Arkansas and along the southeastern coastal plain.

Prior climate studies failed to recognize most past incidents because climate researchers usually look at averages of heat and humidity measured over large areas and over several hours at a time. Raymond and his colleagues instead drilled directly into hourly data from 7,877 individual weather stations, allowing them to pinpoint shorter-lived bouts affecting smaller areas.

... Prior studies suggest that even the strongest, best-adapted people cannot carry out normal outdoor activities when the wet bulb hits 32 C, equivalent to a heat index of 132 F. Most others would crumble well before that. A reading of 35—the peak briefly reached in the Persian Gulf cities—is considered the theoretical survivability limit. That translates roughly to a heat index of 160 F. (The heat index actually ends at 127 F, so these readings are literally off the charts.) "It's hard to exaggerate the effects of anything that gets into the 30s," said Raymond.

The study found that worldwide, wet-bulb readings approaching or exceeding 30C on the wet bulb have doubled since 1979. The number of readings of 31— previously believed to occur only rarely—totaled around 1,000. Readings of 33—previously thought to be almost nonexistent—totaled around 80.

C. Raymond el al., "The emergence of heat and humidity too severe for human tolerance," Science Advances (2020).
https://advances.sciencemag.org/content/6/19/eaaw1838
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sidd

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Re: Heatwaves
« Reply #433 on: May 12, 2020, 10:36:57 PM »
Re: Coffel (2018 doi: 10.1088/1748-9326/aaa00e )

Coffel calculates change of monthly mean daily max T at each grid cell:

"Future changes in monthly-mean daily maximum temperature and wet bulb temperature, relative to
1985–2005, are calculated at each grid cell for each GCM and emission scenario in each year between
2020 and 2080."

"We calculate the relative frequency of future heat events for each GCM grid cell as the mean number of days per year during 2060–2080 which exceed the mean annual maximum temperature and wet bulb temperature for the same GCM during the modeled 1985–2005 period."

"If the GCM wet bulb temperature at a given grid cell exceeds a threshold value (e.g. a wet bulb of 32 ◦ C or 35 ◦ C) on a given day, the grid cell is considered exposed"

sidd

blumenkraft

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Re: Heatwaves
« Reply #434 on: May 13, 2020, 08:30:46 AM »
If you are wondering why Sidd cites the Coffel paper, it's the continuation of a talk starting in the Economic Inequality thread around here >>


vox_mundi

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Re: Heatwaves
« Reply #435 on: May 27, 2020, 11:20:21 AM »
India Wilts Under Heatwave as Temperature Hits 50 Degrees Celsius
https://phys.org/news/2020-05-india-wilts-heatwave-temperature-degrees.html

India is wilting under a heatwave, with the temperature in places reaching 50 degrees Celsius (122 degrees Fahrenheit) and the capital enduring its hottest May day in nearly two decades.

The hot spell is projected to scorch northern India for several more days, the Meteorological Department said late Tuesday, "with severe heat wave conditions in isolated pockets".

Met officials said Churu in the northern state of Rajasthan was the hottest place on record on Tuesday, at 50 Celsius, while parts of Punjab, Haryana and Uttar Pradesh sweltered in the high 40s.

Parts of the capital, New Delhi, recorded the hottest May day in 18 years with the mercury hitting 47.6 Celsius.

The country of 1.3 billion people suffers from severe water shortages with tens of millions lacking running water—to say nothing of air conditioning.

Parts of Delhi and elsewhere regularly see scuffles when tankers arrive to deliver water. Last year Chennai made international headlines when the southern city ran out of water entirely.

The heatwave adds to problems the country already has dealing with the spread of coronavirus.

India now has the 10th highest number of coronavirus cases globally, climbing above 150,000 on Wednesday with almost 4,500 deaths.

Last week cyclone Amphan killed more than 100 people as it ravaged in eastern India and Bangladesh, flattening villages, destroying farms and leaving millions without power.

Huge swarms of desert locusts, meanwhile, have destroyed nearly 50,000 hectares (125,000 acres) of crops across western and central India, and may enter Delhi in coming days.

The north-eastern states of Assam and Meghalaya are also currently experiencing floods, with more heavy rainfall forecast in the coming days.
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vox_mundi

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Re: Heatwaves
« Reply #436 on: May 28, 2020, 11:41:45 PM »
Montreal Breaks May Temperature Record As Heatwave Grips Canada
https://phys.org/news/2020-05-montreal-temperature-heatwave-canada.html

Temperatures in Montreal on Wednesday reached an all-time high for the month of May as a heatwave swept through parts of Canada, Environment Canada said.

At Montreal's Pierre Elliott Trudeau international airport, the mercury rose to 36.6 degrees Celsius (98 Fahrenheit), making the city the hottest in the country.

It was also the second-highest temperature on record overall behind 37.6C (100F) set in August 1975. The previous record for May of 34.7C (94.5F) was set in 2010.

In neighboring Ontario, Ottawa also hit a record 35C (95F)—but with the humidity Environment Canada said it felt like 40C (104F) in both cities.

And in Toronto, a half dozen cooling centers were opened for residents as authorities issued extreme heat warnings.
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Aluminium

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Re: Heatwaves
« Reply #437 on: June 20, 2020, 04:33:13 PM »

kassy

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Re: Heatwaves
« Reply #438 on: June 20, 2020, 04:57:00 PM »
Some really impressive numbers there. Can´t be good in the long term.
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Re: Heatwaves
« Reply #439 on: June 20, 2020, 06:12:06 PM »
I wonder, how many heatwaves would it take for permafrost to melt there? Siberia has had hot weather in summers in the past too, but 2020 seems to be on a new level in that region there.

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Re: Heatwaves
« Reply #440 on: June 20, 2020, 07:06:49 PM »
The amount of heatwaves is not important for that, more the amount of total warming. It already melts every year and if i recall correctly at least in (parts of) Siberia it hardly refreezes during winter already. 

Off course this only relates to the top layer and there is much more permafrost below so it is not really practical to look at heatwaves. What is interesting is to see if these heatwaves in certain regions tend to reoccur (but that is a WIP).

 
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Aluminium

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Re: Heatwaves
« Reply #441 on: June 20, 2020, 09:28:11 PM »
Winters are still cold there. -50°С is common. Yakuts eat ice cream in this conditions. They say that ice cream becomes more solid like cookie.

Tom_Mazanec

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Re: Heatwaves
« Reply #442 on: June 20, 2020, 11:53:58 PM »
I like soft ice cream, so I can gush it around in my mouth.

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Re: Heatwaves
« Reply #443 on: June 21, 2020, 06:51:03 AM »
Re: does permafrost melt in Siberia

Quote from: kassy
The amount of heatwaves is not important for that, more the amount of total warming. It already melts every year and if i recall correctly at least in (parts of) Siberia it hardly refreezes during winter already.
(bolding by me)

I was surprised because, if it melts every year, that would mean that there's no permafrost anymore.

From: https://en.wikipedia.org/wiki/Permafrost
"Permafrost is ground that continuously remains frozen for two or more years, located on land or under the ocean. Permafrost does not have to be the first layer that is on the ground. It can be an inch to over miles deep into the Earth's surface."
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wili

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Re: Heatwaves
« Reply #444 on: June 21, 2020, 08:03:33 AM »
Yes, some are now using the term 'perma-melt'  :'(
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kassy

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Re: Heatwaves
« Reply #445 on: June 21, 2020, 06:29:59 PM »
Re: does permafrost melt in Siberia

I was surprised because, if it melts every year, that would mean that there's no permafrost anymore.
It is usually a very thick layer so it is only the top that melts.


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Re: Heatwaves
« Reply #446 on: June 22, 2020, 06:10:55 AM »
The top layer that melts is the active layer. That is not permafrost as you can see on the graph I posted above.
It is not to bug you kassy, but for better understanding here.

That permafrost temperatures are rising fast is ominous. If temps go above zero °C part of the year (melting) that means that the layer is active and is no longer called permafrost.
A geographical permafrost region does not necessarily include the top layer. With rising temps, the permafrost table becomes lower.
If I am wrong in this, please correct me.

I realise that this is off topic here. Sorry.
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jens

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Re: Heatwaves
« Reply #447 on: June 22, 2020, 08:20:47 AM »
Eastern Siberia is also generally colder than western Siberia, so I assume it would take more heating for things to start melting there. But obviously ultimately no place is safe, it's just the question of what are the tipping points.

kassy

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Re: Heatwaves
« Reply #448 on: June 22, 2020, 10:13:45 AM »
See the Permafrost General Science thread for more about the permafrost.
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oren

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Re: Heatwaves
« Reply #449 on: June 24, 2020, 10:47:41 AM »

What site provides this particular graphic? I like it.