Support the Arctic Sea Ice Forum and Blog

Author Topic: Temperature signals from Covid-19  (Read 2982 times)

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Temperature signals from Covid-19
« on: May 02, 2020, 12:30:04 AM »
What kind of climate signals should we expect from the lockdown policies related to Covid-19?

We know that economic activity is down a lot, there is a global recession/depression.

CO2 emissions down, but CO2 levels at Mauna Loa increasing.

Will be interesting to follow temperature developments. Will the recession, the increadible decrease in economic activity, in travel, in transport have any effect on global temperatures?

The null hypothesis is that temperatures will follow CO2 up.

I was playing around with temperature and CO2 data at woodfortrees, and created the attached graph.

We have an interesting temperature signal in the UAH6 temperatures, going down in April.
Hadcrut isn't updated yet.

https://woodfortrees.org/plot/uah6/from:2015/plot/hadcrut4gl/from:2015/plot/esrl-co2/from:2015/normalise

Florifulgurator

  • Frazil ice
  • Posts: 304
  • Virtual world alter ego / अवतार of Martin Gisser
    • View Profile
  • Liked: 141
  • Likes Given: 87
Re: Temperature signals from Covid-19
« Reply #1 on: May 02, 2020, 01:25:28 AM »
CO2 emissions down, but CO2 levels at Mauna Loa increasing.
Because it's the seasonal upswing. But I see some flattening of the upswing curve... Need to wait another month to see if this is significant.
Google image search on my avatar image gives "wood". In fact it is the lower part of David Hilbert's tombstone.

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #2 on: May 02, 2020, 02:33:22 AM »
What makes the case for a temperature signal from C19 somewhat stronger, is that we see this signal mainly on the Northern hemisphere, where the economic downturn effects are supposedly much stronger than on the less affected SH.

April  Temperatures (preliminary)
Global composite temp.: +0.38 C (+0.68 °F) above seasonal average
Northern Hemisphere: +0.43 C (+0.77 °F) above seasonal average
Southern Hemisphere: +0.34 C (+0.61 °F) above seasonal average
Tropics: +0.45 C (+0.81°F) above seasonal average

March Temperatures (Final)
Global composite temp.: +0.48 C (+0.86 °F) above seasonal average
Northern Hemisphere: +0.61 C (+1.10 °F) above seasonal average
Southern Hemisphere: +0.34 C (+0.61 °F) above seasonal average
Tropics: +0.63 C (+1.13°F) above seasonal average

https://www.nsstc.uah.edu/climate/2020/april2020/GTR_202004Apr_1.pdf

etienne

  • Nilas ice
  • Posts: 1001
    • View Profile
    • About energy
  • Liked: 151
  • Likes Given: 3
Re: Temperature signals from Covid-19
« Reply #3 on: May 02, 2020, 10:35:50 AM »
Maybe this could simply come of a lower fossil fuels consumption, less burning means less heat produced. I really am not a specialist, but my understanding is that we are in a heating process, which means that the temperature is lower that what it should be with the greenhouse gas concentration we have because of the inertia of the system.

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #4 on: May 02, 2020, 02:30:52 PM »
Maybe this could simply come of a lower fossil fuels consumption, less burning means less heat produced. I really am not a specialist, but my understanding is that we are in a heating process, which means that the temperature is lower that what it should be with the greenhouse gas concentration we have because of the inertia of the system.

IIRC the amount of heat generated by humans burning fossile fuels is negligible compared to the GHG effect.

I was expecting to see a rise in temperatures due to C-19, not a decline.
We have gotten much cleaner skies, there is maybe only 10% of air traffic left, no contrails, no soot, no smoke, no haze compared to what we were used to.

Thus the smaller amount of aerosols would reflect less of the sun's insolation, and we would get higher temperatures.

So why hasn't that happened?

kassy

  • Moderator
  • Nilas ice
  • Posts: 2189
    • View Profile
  • Liked: 1182
  • Likes Given: 896
Re: Temperature signals from Covid-19
« Reply #5 on: May 02, 2020, 02:34:09 PM »
I wonder if we even see a CO2 related Covid signal in temperatures.

That last fall (or slowdown) of CO2 growth was after the housing/banking crisis but is there any paper that works out a temp change from that slowdown?


The deceiving thing about the big, historic drop in CO2 emissions

...

This is all likely true. We’re headed for some major emission declines. But, critically, the true number global warming cares about — the amount of carbon dioxide saturating the atmosphere — will barely be impacted by an unprecedented drop in carbon emissions this year, a drop the International Energy Agency estimates at nearly eight percent (compared with historic 2019 levels).

That’s because atmospheric CO2 levels are like a massive bank account that’s been accruing more and more carbon every year for well over a century (this bank account is now at its highest levels in at least 800,000 years, but more likely millions of years). This year’s carbon emissions, however, are just a deposit. This 2020 deposit may be smaller than in 2019, but it’ll still add to the atmospheric CO2 bank account.

...

“We’re still emitting 92 percent of a very, very large number,” said Kristopher Karnauskas, a climate scientist at the University of Colorado Boulder.

This means, by year’s end, we’ll be puffing about the same amount of carbon into the atmosphere as we were in 2010. Yes, we’ll still be adding over 30 gigatonnes — or 30 billion metric tons — of CO2 to the atmosphere this year.

...

To illustrate, before the pandemic and ensuing economic shock, Earth’s average atmospheric CO2 concentration was expected to average around 414.2 parts per million, or ppm, this year. With a five percent drop in emissions, this would fall to just 414.0 ppm, explained Hausfather. And with an eight percent emissions reduction, it would drop slightly more to around 413.9 ppm. Importantly, this is still much higher than average CO2 concentrations last year, which averaged 411.5 ppm.

...

“It’s only transportation that has changed radically,” explained Rob Jackson, a professor of earth system science at Stanford University and director of the Global Carbon Project, which researches carbon emissions. “Outside of transportation, emissions are not changing all that much,” he said. For example, we’re still using lots of electricity at home.

https://mashable.com/article/carbon-emissions-drop-2020-coronavirus

The easier detected changes are related to aerosol reductions.
1) There was already going to be an effect from ´cleaner´ shipping fuels. This effect much be much stronger with less shipping overall.

But IIRC the effect is quite local so reduction in Atlantic shipping might be more important then reduction in ships going from China to the US via the Pacific ocean?

2) Then there is a reduction from factories closing temporarily but i have seen no good breakdowns of these.

And maybe

3) Clearer skies. They have been quite remarkable in the Netherlands although the weather has ruined it this week. Then again that might not do that much see:
https://www.int-res.com/articles/cr2004/26/c026p001.pdf
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.

Bruce Steele

  • Nilas ice
  • Posts: 1784
    • View Profile
  • Liked: 436
  • Likes Given: 16
Re: Temperature signals from Covid-19
« Reply #6 on: May 02, 2020, 05:13:18 PM »
There is an annual spring cycle of CO2 intake by phytoplankton and terrestrial plants . The CO2 absorbed by plants is released in the fall as those plants die. Drought can affect the amount of CO2 emissions and that is why El Niño shows up in the CO2 long term charts.
 Now this next part is pure conjecture but what if the sudden clear skies are promoting plant growth that we didn’t realize had been suppressed ? The signal should show up in atmospheric CO2 dropping more than would be expected from emissions drops incurred from Covid lockdown  reductions alone.
 





blumenkraft

  • Young ice
  • Posts: 4849
  • Fans of Hans Ø Club - circa 2018
    • View Profile
  • Liked: 1694
  • Likes Given: 2772
Re: Temperature signals from Covid-19
« Reply #7 on: May 02, 2020, 05:16:12 PM »
Good point, Bruce.
“I’m an introvert. I’m just different that’s all. I’m so sorry. I don’t have a gun. I don’t do that stuff... All I was trying to do was to become better. I’ll do it... You all are phenomenal. You are beautiful. And I love you. Try to forgive me. I’m sorry.”

Elijah McClain

Bruce Steele

  • Nilas ice
  • Posts: 1784
    • View Profile
  • Liked: 436
  • Likes Given: 16
Re: Temperature signals from Covid-19
« Reply #8 on: May 02, 2020, 05:50:33 PM »
Just a first look but smog can reduce photosynthetic productivity by 10-40% . Probably better sources out there but first article I found.

http://nbrienvis.nic.in/Database/1_2051.aspx

oren

  • First-year ice
  • Posts: 5833
    • View Profile
  • Liked: 1976
  • Likes Given: 1734
Re: Temperature signals from Covid-19
« Reply #9 on: May 02, 2020, 06:39:41 PM »
Has there been any official measure of the increased insolation? Are solar plants giving better output? I wonder if anyone can find quantitative measures of the effects of less pollution.

Pmt111500

  • Nilas ice
  • Posts: 2189
  • Yes, I do not always bicycle
    • View Profile
  • Liked: 196
  • Likes Given: 132
Re: Temperature signals from Covid-19
« Reply #10 on: May 02, 2020, 06:52:12 PM »
Count in reduced air travel and reduced condensation trails. Only flying objects I've seen here last month have been couple of helicopters and the coast guard's plane. Prior Covid it was quite common to see 5  lines crossing the sky, popular routes to far east Asia from Northern part of Europe and North Americans going Middle East cross nearby.
Cooling the outside by heat pump.

dnem

  • Grease ice
  • Posts: 556
    • View Profile
  • Liked: 259
  • Likes Given: 156
Re: Temperature signals from Covid-19
« Reply #11 on: May 02, 2020, 07:57:56 PM »
Has there been any official measure of the increased insolation? Are solar plants giving better output? I wonder if anyone can find quantitative measures of the effects of less pollution.

Funny, my wife and I were just discussing this on our walk today. The quality of the light here today is remarkably bright and vivid.  I'm not sure about the best way to do this, as obviously weather will swamp any clean air effect, and I'd need to compare day of year against day of year (or at least relatively small chunks). My array reports total output by 5 minute increments. I thought I'd look at peak daily 5-minute output as a proxy for clarity effect. I'll need to play around. Any suggestions for how to tease it out?

Bruce Steele

  • Nilas ice
  • Posts: 1784
    • View Profile
  • Liked: 436
  • Likes Given: 16
Re: Temperature signals from Covid-19
« Reply #12 on: May 02, 2020, 08:06:14 PM »
PAR , photosynthetic available radiation in the wavelengths that plants utilize needs some research. I found a dataset I think but I can’t navigate the site. Data from 2004 to present it says .

https://data.noaa.gov/dataset/dataset/ow-nasa-modis-photosynthetically-available-radiation-par1

Maybe still being developed ?

oren

  • First-year ice
  • Posts: 5833
    • View Profile
  • Liked: 1976
  • Likes Given: 1734
Re: Temperature signals from Covid-19
« Reply #13 on: May 02, 2020, 10:35:07 PM »
Quote
I thought I'd look at peak daily 5-minute output as a proxy for clarity effect. I'll need to play around. Any suggestions for how to tease it out?
Good idea.
If you can find several years of the same date with no clouds, a chart of peak daily output might show a slightly deteriorating trend, and a potential uptick this year.
I think it best to make a chart of each date over the years, and look for those charts (if any) that show the above behavior.
How many years im your records?

Tom_Mazanec

  • Young ice
  • Posts: 3146
    • View Profile
    • Planet Mazanec
  • Liked: 590
  • Likes Given: 219
Re: Temperature signals from Covid-19
« Reply #14 on: May 03, 2020, 05:10:59 PM »
Same here, skies much clearer.
I look forward to getting the results of this in the temperatures.
SHARKS (CROSSED OUT) MONGEESE (SIC) WITH FRICKIN LASER BEAMS ATTACHED TO THEIR HEADS

Niall Dollard

  • Grease ice
  • Posts: 726
    • View Profile
  • Liked: 301
  • Likes Given: 63
Re: Temperature signals from Covid-19
« Reply #15 on: May 05, 2020, 10:23:08 AM »
The Copernicus EU global surface temperatures for April 2020 are out now.

April 2020 was joint warmest.

Western Siberia stands out for warmth. Central Canada for cold anomalies - but warm far exceeds the cold.

Niall Dollard

  • Grease ice
  • Posts: 726
    • View Profile
  • Liked: 301
  • Likes Given: 63
Re: Temperature signals from Covid-19
« Reply #16 on: May 05, 2020, 10:49:18 AM »
Looking back with months to Dec 19 (Pre and Post Covid) I find it difficult to attribute a Covid 19 imprint on these (Copernicus EU) global surface temps.

Dec 19 - Joint warmest on record

Jan 20 - Warmest on record

Feb 20 - Second warmest

Mar 20 - Joint 2nd/3rd warmest

Apr 20 - Joint warmest.

In other words, irrespective of Covid 19, globally each month is on a par with warmest or second warmest.

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #17 on: May 10, 2020, 06:55:07 AM »
The Copernicus EU global surface temperatures for April 2020 are out now.

April 2020 was joint warmest.
...

Supposedly, the satellite data are the correct ones...

Could this really big difference between satellite data and more ground-based data like Copernicus (which is a blend of various joined and averaged data, including also satellite), be related to lower temps in urban heat islands (UHI's) and micro-UHI areas due to less activity during Coronavirus lock-down?

The primary contributors to UHI are buildings, roads and parking lots. If asphalt is uncovered by cars during lockdowns, the UHI effect will get larger.

Satellite data don't suffer from poor siting, like land-based temperature data, that to some degree are located near UHI's. The correction factors for UHI might now be too small.

Attach updated chart, with April data from UAH6.

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #18 on: May 26, 2020, 08:39:49 PM »
Temperature anomalies continue down. These are daily data compiled at the linked site.
The drop is more pronounced in the NH, from March and onwards.

https://oz4caster.wordpress.com/cfsr/
« Last Edit: May 26, 2020, 10:13:40 PM by Hefaistos »

Bruce Steele

  • Nilas ice
  • Posts: 1784
    • View Profile
  • Liked: 436
  • Likes Given: 16
Re: Temperature signals from Covid-19
« Reply #19 on: May 26, 2020, 08:57:00 PM »
NH arctic amplification shows up during fall to winter months and the current season looks similar to last year. If we are expecting aerosols to have a large impact it doesn’t seem obvious in the temperatures. It is nice having clear skies and so little air traffic but the jury is still out on aerosol cooling effects.
 

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #20 on: May 26, 2020, 10:00:48 PM »
NH arctic amplification shows up during fall to winter months and the current season looks similar to last year. If we are expecting aerosols to have a large impact it doesn’t seem obvious in the temperatures. It is nice having clear skies and so little air traffic but the jury is still out on aerosol cooling effects.

If you remove the aerosols, we expect to get a warming effect. Instead we have a drop in anomalies in the NH (where lockdown effects are more pronounced) from 1.8 in beginning of March (when lockdowns started) to 0.6 today, which is a really big drop of 1.2 K.
So, what's going on here?

FrostKing70

  • Frazil ice
  • Posts: 163
    • View Profile
  • Liked: 34
  • Likes Given: 13
Re: Temperature signals from Covid-19
« Reply #21 on: May 27, 2020, 12:20:40 AM »
I think Kassy has it right. 

CO2 is still increasing, just not as fast as 2019.  There should be a slight increase in temperature due to a reduction in aersols (sp?).  Then the seasonal changes in CO2.

Bruce Steele

  • Nilas ice
  • Posts: 1784
    • View Profile
  • Liked: 436
  • Likes Given: 16
Re: Temperature signals from Covid-19
« Reply #22 on: May 27, 2020, 02:22:25 AM »
Hefaistos, If I might offer my view on both your the carbon cycle post and the temperature anomaly chart . The carbon cycle has to keep increasing it’s uptake of CO2 each year as we increase emissions. Each spring plants and phytoplankton need to sink larger amounts of CO2 but some sinks are short lived and some the CO2 captured in spring is then released in the fall / winter.  Excuse the conjecture but I think the large increases of organic matter in spring is followed with large amounts of remineralization and CO2 emissions in the fall. So annual swings in temperature and CO2 should increase while the 365 day anomaly changes more slowly.
 The long term efficacy of the system is how much CO2 can be sunk into long term sinks. Those amounts are limited in the carbonate sink by the amount of seafloor above the aragonite horizon and as the aragonite horizon shoals there is less and less area where carbonates can settle into sinks that can last millions of years. Any remineralized  organic matter or carbonates that dissolve re-enter the ocean DIC ( dissolved inorganic carbon )  pool but that carbon pool is shorter lived. About a thousand years.
 
 
« Last Edit: May 27, 2020, 07:08:52 AM by Bruce Steele »

Human Habitat Index

  • Frazil ice
  • Posts: 197
    • View Profile
  • Liked: 34
  • Likes Given: 117
Re: Temperature signals from Covid-19
« Reply #23 on: May 27, 2020, 02:40:35 AM »
The lessening of aerosol masking leads to less clouds which causes higher temps during the day and lower temps at night.

Do the night's decrease temp partially cancel the higher day temps ?

Giving us a misleading picture.
There is a principle which is a bar against all information, which cannot fail to keep a man in everlasting ignorance. That principle is contempt prior to investigation. - Herbert Spencer

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #24 on: May 27, 2020, 06:31:50 AM »
The lessening of aerosol masking leads to less clouds which causes higher temps during the day and lower temps at night.

Do the night's decrease temp partially cancel the higher day temps ?

Giving us a misleading picture.

Temperatures are read 4 times per 24 hours at both GFS and CSFR, so we cover both day and night temps.
Do you want to claim that the cooling effect from the diminished aerosols during nighttime is stronger, than the warming effect during daytime?
What's the theory behind that?

Human Habitat Index

  • Frazil ice
  • Posts: 197
    • View Profile
  • Liked: 34
  • Likes Given: 117
Re: Temperature signals from Covid-19
« Reply #25 on: May 27, 2020, 06:42:36 AM »
The lessening of aerosol masking leads to less clouds which causes higher temps during the day and lower temps at night.

Do the night's decrease temp partially cancel the higher day temps ?

Giving us a misleading picture.

Temperatures are read 4 times per 24 hours at both GFS and CSFR, so we cover both day and night temps.
Do you want to claim that the cooling effect from the diminished aerosols during nighttime is stronger, than the warming effect during daytime?
What's the theory behind that?

Just wanted to know if possible extra night coldness affects the mean temp and if it is relevant to the discussion.
There is a principle which is a bar against all information, which cannot fail to keep a man in everlasting ignorance. That principle is contempt prior to investigation. - Herbert Spencer

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #26 on: May 27, 2020, 09:07:15 AM »
NH arctic amplification shows up during fall to winter months and the current season looks similar to last year. If we are expecting aerosols to have a large impact it doesn’t seem obvious in the temperatures. It is nice having clear skies and so little air traffic but the jury is still out on aerosol cooling effects.

Bruce, there is no factual evidence of an increase in Arctic amplification.
Yes, there is a deviation from trend, but for March and April this deviation is similar to previous years. More like a parallell offset from the baseline.

Here's a graph with the monthly plot for the latest years, and for the first 4 months of 2020, compared to the reference period.

I can't see how this could explain the big drop in temperatures during the  C19 lockdown period from March 2020.

nanning

  • Nilas ice
  • Posts: 2080
  • 0Kg CO₂, 37 KWh/wk,125L H₂O/wk, No offspring
    • View Profile
  • Liked: 323
  • Likes Given: 17319
Re: Temperature signals from Covid-19
« Reply #27 on: May 27, 2020, 10:33:42 AM »
To wit:
From: https://en.wikipedia.org/wiki/Polar_amplification#Amplification_factor
Quote
Polar amplification is quantified in terms of a polar amplification factor, generally defined as the ratio of some change in a polar temperature to a corresponding change in a broader average temperature:
"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?

wolfpack513

  • Frazil ice
  • Posts: 220
    • View Profile
  • Liked: 92
  • Likes Given: 32
Re: Temperature signals from Covid-19
« Reply #28 on: May 27, 2020, 03:16:02 PM »
Come on guys the CO2 impact from COVID-19 & the impact on global temperatures is so minuscule it's noise at best.  The fact that you think will be able to track it month-by-month global mean temps affects is silly.

You realize that CO2 concentration growth year-over-year is responsible for an additional radiative forcing of like ~0.03 W/M².  Estimates have 2020 *annual* emissions down 7%.  That's doesn't even account for all anthropogenic CO2: land use changes, etc..  Regardless, that 7% drop in emissions due to COVID-19 is a drop in radiative forcing of  ~0.00021 W/M².

Also what's the obsession with satellite data?  Surface temperature data is way more accurate for global mean estimates.  You realize that satellite data goes through massive algorithms & corrections because of changes in orbits & time of day passes.

The focus should be on aerosols not CO2 concentration changes when talking about COVID-19.

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #29 on: June 01, 2020, 10:35:38 AM »
Come on guys the CO2 impact from COVID-19 & the impact on global temperatures is so minuscule it's noise at best.  The fact that you think will be able to track it month-by-month global mean temps affects is silly.

You realize that CO2 concentration growth year-over-year is responsible for an additional radiative forcing of like ~0.03 W/M².  Estimates have 2020 *annual* emissions down 7%.  That's doesn't even account for all anthropogenic CO2: land use changes, etc..  Regardless, that 7% drop in emissions due to COVID-19 is a drop in radiative forcing of  ~0.00021 W/M².

Also what's the obsession with satellite data?  Surface temperature data is way more accurate for global mean estimates.  You realize that satellite data goes through massive algorithms & corrections because of changes in orbits & time of day passes.

The focus should be on aerosols not CO2 concentration changes when talking about COVID-19.

Hi Wolfpack.
The title of this thread is "Temperature signals from C19". I of course don't expect any change in CO2 at all because of C19.
I said in the first post that I expect temperatures to rise, because of strongly diminished aerosols, and a continued increase in CO2. Instead they have fallen strongly, at least the sat. data.

I don't agree with you that surface temperature data is more accurate. The satellite data that measures temperatures in all of the LT give a richer measure than surface only data.

All temperature datasets we have go through algorithms/processing. You want to claim that the high precision, finely tuned and continously evaluated satellite data is somehow giving us the wrong temperatures? Something wrong in the algos?

Then please give a reference to that claim!! Because it would be sensational if it was true.
Or at least maybe you would care to present a hypothesis, what causes the satellite data to be faulty!

wolfpack513

  • Frazil ice
  • Posts: 220
    • View Profile
  • Liked: 92
  • Likes Given: 32
Re: Temperature signals from Covid-19
« Reply #30 on: June 03, 2020, 02:27:02 PM »
When you start a new thread the opening post matters.  It's 2020 & you seem surprised that CO2 concentration is up even though emissions are down.  CO2 ACCUMULATES IN THE ATMOSPHERE! This is AGW 101. 

The current warming rate is roughly +0.20°C per decade.  That's an alarming rate but on a monthly basis worth: +0.0017°C per month.  Global mean temps monthly variability (largely ENSO) is ~0.50°C.  That's 2 orders of magnitude higher than the background warming rate!

We already have several threads on aerosols as well as CO2 concentration, CO2 emissions, CO2 equivalent and a thread on tracking global mean temps.


What kind of climate signals should we expect from the lockdown policies related to Covid-19?

We know that economic activity is down a lot, there is a global recession/depression.

CO2 emissions down, but CO2 levels at Mauna Loa increasing.

Will be interesting to follow temperature developments. Will the recession, the increadible decrease in economic activity, in travel, in transport have any effect on global temperatures?

The null hypothesis is that temperatures will follow CO2 up.

I was playing around with temperature and CO2 data at woodfortrees, and created the attached graph.

We have an interesting temperature signal in the UAH6 temperatures, going down in April.
Hadcrut isn't updated yet.

https://woodfortrees.org/plot/uah6/from:2015/plot/hadcrut4gl/from:2015/plot/esrl-co2/from:2015/normalise

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #31 on: June 04, 2020, 07:27:35 AM »
When you start a new thread the opening post matters.  It's 2020 & you seem surprised that CO2 concentration is up even though emissions are down.  CO2 ACCUMULATES IN THE ATMOSPHERE! This is AGW 101. 

If you read my first post, you also might have noticed that there was a chart attached? In that chart there was a blue line, showing the rising trend of CO2 level in the atmosphere. Thanks, but I knew that :) My point was just to emphasize that we're seeing a drop in LT temperatures in spite of the increased level of CO2. Forcing is up, LT temperatures down.

Quote
The current warming rate is roughly +0.20°C per decade.  That's an alarming rate but on a monthly basis worth: +0.0017°C per month.  Global mean temps monthly variability (largely ENSO) is ~0.50°C.  That's 2 orders of magnitude higher than the background warming rate!

On the background of a trend of rising temperatures, we have a negative temperature anomaly signal in the satellite data since about February (different satellites show the same). Part of that might be a seasonal drop, although i wouldn't bet on it, as there is no stable pattern here if you look at temperature data from year to year.

Quote
We already have several threads on aerosols as well as CO2 concentration, CO2 emissions, CO2 equivalent and a thread on tracking global mean temps.

I know that this forum has quite a few threads.
But this is the thread about the eventual temperature signals from Covid-19.
This is something totally unique happening in the world, with a recession/depression hitting in no time at all, and massive drops in the aerosols, especially in the NH.
We're still looking for temperatures to rise, but what if they continue to fall? Might it be due to the economic and environmental effects of C19?

Niall Dollard

  • Grease ice
  • Posts: 726
    • View Profile
  • Liked: 301
  • Likes Given: 63
Re: Temperature signals from Covid-19
« Reply #32 on: June 04, 2020, 11:05:43 AM »
Hefaistos, I dont really have any problem with you starting this thread. It is worthwhile to explore the relationship between global temperatures and recent downturn in economic activity (because of Covid-19).

But I do have a difficulty using UAH as a metric. I know many people have reservations about Roy Spencer's data series and methods employed to generate it. There have already been several revisions/adjustments since 1979 so I find it difficult to compare say 1980 anomalies with those of UAH ver 6.0.

But that's another topic.

If we just look at more recent years only, I can see two issues.

1) There is a trend during the months of the year, with anomalies typically falling in the spring (March April and then rising in the summer. (see 2017 and 2018).

2) UAH is heavily influenced by ENSO. Years of strong El Nino like 2016, the yearly pattern observed in 2017 and 2018 is not seen.

So coming back to 2020. The graph in the first post shows the UAH up to March 2020 and the trend of it falling through the spring is there again into April. Since then we now have the UAH May figure which shows a rise again (up tick in May 2020 added).

I think you cannot see the wood (Covid-19 effects) for the trees (because of the usual UAH seasonal (ENSO) and monthly variations).


Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #33 on: June 04, 2020, 12:36:15 PM »
Hefaistos, I dont really have any problem with you starting this thread. It is worthwhile to explore the relationship between global temperatures and recent downturn in economic activity (because of Covid-19).

But I do have a difficulty using UAH as a metric. I know many people have reservations about Roy Spencer's data series and methods employed to generate it. There have already been several revisions/adjustments since 1979 so I find it difficult to compare say 1980 anomalies with those of UAH ver 6.0.
...

Neil, if you don't like the satellite that feeds the UAH6 with data for this reason, you can choose another satellite.
There is e.g. RSS MSU, also available at WoodForTrees, which afaik is from a different satellite(s). Here's a plot of the both together. As you can see, the data are practically identical, except for a baseline shift. (UAH6 is the lower one, I shifted it up by 0.3 to bring them to the same level).

These satellite data are the highest quality temperature data we can get, and I think it further ads to their value that they are not measured only at 2 m surface, but for the entire LT. They give a more accurate manifestation of the thermal energy in the atmosphere, than the surface-only data does.

Here is a nice and very informative wikipedia article comparing the different satellite data, and also discussing how they relate to surface data.

https://en.wikipedia.org/wiki/Microwave_Sounding_Unit_temperature_measurements
« Last Edit: June 04, 2020, 01:11:53 PM by Hefaistos »

Niall Dollard

  • Grease ice
  • Posts: 726
    • View Profile
  • Liked: 301
  • Likes Given: 63
Re: Temperature signals from Covid-19
« Reply #34 on: June 04, 2020, 02:20:15 PM »


These satellite data are the highest quality temperature data we can get, and I think it further ads to their value that they are not measured only at 2 m surface, but for the entire LT. They give a more accurate manifestation of the thermal energy in the atmosphere, than the surface-only data does.


No. I disagree that it is of high quality and accuracy.

Some of the problems they have struggled with relate to satellite altitudes (they slowly fall over their lifetimes, and this orbital decay biases the readings); satellite drift (their orbits shift east-west a small amount causing an error); they errantly include stratosphere temperatures in their lower atmosphere readings; and they have incorrect temperature calibration on the satellites.

And it is very sensitive/dominated by El Nino conditions. I contend that small changes over the Pacific would hide any probable Covid-19 temperature signal.

Spencer attributes the March 2020 decrease to cooling over the central Pacific :

Notes on data released May 2, 2020 (v6.0)

"Seasonally-adjusted temperatures dropped a bit in the tropics and northern hemisphere
from March values leading to a global temperature departure from average of +0.38 °C
(+0.68 °F). As indicated last month we suggested that the drop is due in part to the cooling
of the central Pacific Ocean. "

https://www.nsstc.uah.edu/climate/2020/april2020/GTR_202004Apr_1.pdf






Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #35 on: June 05, 2020, 12:27:41 AM »

No. I disagree that it is of high quality and accuracy.

Some of the problems they have struggled with relate to satellite altitudes (they slowly fall over their lifetimes, and this orbital decay biases the readings); satellite drift (their orbits shift east-west a small amount causing an error); they errantly include stratosphere temperatures in their lower atmosphere readings; and they have incorrect temperature calibration on the satellites.

And it is very sensitive/dominated by El Nino conditions. I contend that small changes over the Pacific would hide any probable Covid-19 temperature signal.

...

All these factors regarding satellite data are well-known and nothing that invalidates the data, as corrections are made and the quality of the data is continously improved.

OK, if you don't like pure sat data like UAH6 or RSS, we can look at composite data like the CFSR reanalysis product instead. It also contains a load of sat data, but mixed with other data sources.
The latest version of CFSR, based on CFSv2, is described in this paper:
https://journals.ametsoc.org/doi/10.1175/JCLI-D-12-00823.1

Attached is a chart with CSFR temperatures since 2014, with moving averages.
You claim that there is some kind of yearly pattern regarding the temperature anomalies, from your previous post:
 
Quote
"1) There is a trend during the months of the year, with anomalies typically falling in the spring (March April and then rising in the summer. (see 2017 and 2018). "

Yes, anomalies are typically higher in the beginning of the year. But they aren't falling as early as in March/April, that seems to come somewhat later, in May/June for the last years, as seen in the chart.

What's totally clear, is that we still have a negative temperature anomaly signal to deal with for the first half of 2020, in spite of the expected positive anomaly signal due to reduced aerosols. (CFSR forecasts the temperature anomaly to drop further.)
2020 shapes up to look like the "coming out of ENSO year" 2016, but possibly with a Covid signal instead of the ENSO signal. Only that the signal has the wrong sign.
« Last Edit: June 05, 2020, 12:40:14 AM by Hefaistos »

Niall Dollard

  • Grease ice
  • Posts: 726
    • View Profile
  • Liked: 301
  • Likes Given: 63
Re: Temperature signals from Covid-19
« Reply #36 on: June 05, 2020, 01:57:25 AM »
I am not sure where this is going Hefaistos. I am of aware of the CFS - but long range modelling is not very trustworthy either.

What is it you are trying to illustrate ? Yes the satellite LT data dipped in March and April and has now gone back upwards in May. Spencer has remarked that the March/April dip  "is due in part to the cooling of the central Pacific Ocean. Recall that in the latter months of 2019, a weak, warm El Niño-like event occurred which aided in warming up the atmosphere for a few months but that impact appears to be fading".

The quoted part is from Spencer's monthly report, not mine. Perhaps there is a Covid signal in there but he hasn't mentioned it. Looking at the previous UAH data it is clear it is sensitive to activity in the Pacific.

The wood for trees satellite graph has not updated for May yet. But I have added in the May UAH anomaly (manually) in my last post above which shows anomaly is rising again and goes against the argument for a negative response.

Meanwhile global surface temperature anomalies continue to remain at a very high or record level.
   

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #37 on: July 01, 2020, 01:35:59 PM »
We have a pronounced negative temperature anomaly signal during the second quarter of 2020.
We expected a positive anomaly signal due to the reduced aerosols as a result of world-wide lockdowns.

So why do we get the opposite?

Attached is a temperature chart, including a forecast for the next week as well.

kassy

  • Moderator
  • Nilas ice
  • Posts: 2189
    • View Profile
  • Liked: 1182
  • Likes Given: 896
Re: Temperature signals from Covid-19
« Reply #38 on: July 01, 2020, 02:19:33 PM »
The signal is mainly from the SH. So i think it is just the normal climate variability at work and that is bigger then whatever the change from Covid is.
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.

Hefaistos

  • Grease ice
  • Posts: 653
    • View Profile
  • Liked: 71
  • Likes Given: 262
Re: Temperature signals from Covid-19
« Reply #39 on: July 18, 2020, 09:36:54 AM »
Clearly, we see no positive temperature signal from the Covid lockdowns.
Anomalies are continuing down, both globally, and for SH and NH, see the chart with GFS weekly forecast (from Karsten Haustein).

I also checked to temperature data for USA, as one country where the lockdown would assumedly bring a more pronounced signal due to high emissions.
But USA also displays a decline in anomalies.
This is UAH6 satellite data for the LT.