Global Surface Air & Sea Temperatures: Current Conditions and Future Prospects

[WYorksWeather]

 Midlands Ice Age Just realised I forgot to reply to this comment.

Full April data will be available later, but in terms of the land vs. ocean issue, we have the following full data for March from Berkeley Earth. March was technically the warmest on record globally, but effectively tied for first.

What's more interesting is the following. Firstly, a map of global temperature rankings. There is nowhere amongst the coldest on record for March, but top 5 warmest areas are also not everywhere of course. But it is notable how much of the warmth is concentrated in the oceans, and also across central Africa and South America.

This is then borne out in the global land and ocean averages. You can see that March was only in 3rd place for the land surface, but a clear first for the ocean surface.

I think the confusion generally comes from the fact that though the oceans have warmed by less than the land surface, they have an outsized impact on the averaging, because of course they make up about 70% of the Earth's surface.

The tropical ocean anomalies are of course typical of El Nino plus background warming, so not anything unusual. What is more unusual is the deviations in the North Atlantic and North Pacific shipping areas, and though this remains an active area of research, the suggestion is that reductions in sulphur emissions have caused at least regional warming in these areas over the past few years. This would also account for faster than expected warming in Europe, for example.

All active areas of research of course, and of course none of this will be settled until we have several more years of data. 

 

 

[danm]

Climate change: World's oceans suffer from record-breaking year of heat

WWW.BBC.CO.UK

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Every single day of the past 12 months has seen a new global sea temperature high for the time of year.

 

[jonboy]

I am going to be controversial. Research shows that the likely impact of hunga tonga due to the stratospheric increase in H2O to be about +0.15Wm-2 radiative forcing this is compared to a forcing of +0.25Wm-2 for the increase in CO2 between the period of 1995 to 2006. Given that the initial plume was located more across the equatorial belt it is no surprise to me that we have seen the oceans warm. we will not see a decline in temperatures until we see this additional water vapor return to earth. Estimates put this at anything from 5 to 10 years. The world is in for a soggy warm few years yet.

The Hunga Tonga‐Hunga Ha'apai Hydration of the Stratosphere - Millán - 2022 - Geophysical Research Letters - Wiley Online Library

 

[Derecho]

10 minutes ago, jonboy said:

m going to be controversial. Research shows that the likely impact of hunga tonga due to the stratospheric increase in H2O to be about +0.15Wm-2 radiative forcing this is compared to a forcing of +0.25Wm-2 for the increase in CO2 between the period of 1995 to 2006. Given that the initial plume was located more across the equatorial belt it is no surprise to me that we have seen the oceans warm. we will not see a decline in temperatures until we see this additional water vapor return to earth. Estimates put this at anything from 5 to 10 years. The world is in for a soggy warm few years yet.

The Hunga Tonga‐Hunga Ha'apai Hydration of the Stratosphere - Millán - 2022 - Geophysical Research Letters - Wiley Online Library

Research indicates that the amount of water vapour added to the atmosphere as a result of that eruption will lead to only +0.035C warming. Global temperatures over the past few months have been around 0.4C higher then what they were in the lead up to that eruption.

Take away the 0.035C and the influence of El Nino and you still get an accelerating warming trend, regardless of whether Hunga Tonga erupted or not.

Did the Tonga undersea volcano eruption cause this year's extreme heat? | Space

WWW.SPACE.COM

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The 2022 Hunga Tonga-Hunga Ha'apai volcano eruption may have contributed to this year's heat, but it's not causing climate change.

 

[jonboy]

 Derecho The paper I posted suggests otherwise

[Derecho]

 jonboy It doesn't it merely states that the eruption at the time won't cool temperatures like most volcanoes do. Yes the increase in stratospheric H2O in that paper is quoted as being +0.15Wm-2, however there was still an increase. There is a cooling influence from this eruption too due to the aerosol radiative forcing.

Hunga Tonga is unique in that this is offset by the warming influence of stratospheric H20 but studies are only estimating this to be a very small figure (0.04C). Some papers even suggest it may have acted as a cooling influence on the southern hemisphere.
 

Just a moment...

AGUPUBS.ONLINELIBRARY.WILEY.COM

So how do you explain that? and if it somehow was responsible, why didn't 2022 see a bump in global temperatures? Why did it happen to occur from June 2023 onwards?

[jonboy]

 Derecho I assume from your comments that you are in the camp of that suggests water vapor has no role whatsoever in warming. In my view such a position is foolhardy. The quoted +0.15Wm-2 is radiative forcing. If you accept that CO2 has a radiative forcing effect then you should accept that water vapor also has a contribution. 

In regard to your last statement I would counter why doesn't CO2 increase have an immediate effect? Its called lag.

[Derecho]

 jonboy I'm not saying water vapour has no role in warming and neither paper is saying that? What I am saying is that the net impact of Hunga Tonga is positive on global temperatures which is exactly what the paper says (and why it's unique). When the cooling influence from aerosol radiative forcing is considered that warming influence is reduced.

Though yes of course some lag is to be expected but it shouldn't be as long as 18 months. The conclusion still stands. Hunga Tonga cannot possibly explain the 0.4C warming we have seen since 2022.

[WYorksWeather]

 jonboy There are two counterbalancing forcings - positive (H20) and negative (SO2).

Edited May 8 by WYorksWeather

[jonboy]

 WYorksWeather There are 2 factors at play. Firstly the 2 forcings are totally different  The SO2 impact which has a cooling effect dissipated below background levels within 12/18 months and the amount injected into the atmosphere was nothing exceptional. Whereas the water vapor was exceptional and is expected to last between 5 and 10 years. It is also clear that the water vapor took some 18 months to impact southern and northern hemispheres and given the lessening impact of the SO2 during that period that is likely to explain the lag.

The cooling effect of SO2 has gone we are left with the warming effect of the excess water vapor which gives the net radiative forcing of +0.15Wm-2 this cannot be ignored when discussing the present warming.

On a side note I see that that volcanic activity around Hunga Tonga is on the increase again perhaps we have not seen the last of this volcano!!  

[Derecho]

 jonboy What you've written here contradicts the below

'We find that the Hunga Tonga-Hunga Ha-apai eruption produced the largest global perturbation of stratospheric aerosols since the Pinatubo eruption in 1991 and the largest perturbation of stratospheric water vapour observed in the satellite era. Immediately after the eruption, water vapour radiative cooling dominated the local stratospheric heating/cooling rates, while at the top-of-the-atmosphere and surface, volcanic aerosol cooling dominated the radiative forcing. However, after two weeks, due to dispersion/dilution, water vapour heating started to dominate the top-of-the-atmosphere radiative forcing, leading to a net warming of the climate system.'

''Particularly strong tropical and Southern Hemispheric impacts on the stratospheric aerosol optical depth place this event on par with the impacts of El Chichon eruption in 1982 in the same latitude bands. The extremely large water vapour availability (more than 100 Tg of water vapour were injected in the stratosphere during the event) was the possible reason for the observed rapid conversion of volcanic SO2 emissions to secondary sulfate aerosols. The large stratospheric water vapour perturbation associated with the HT eruption had also a fundamental role in the plume’s radiative impacts during the first weeks after the eruption, causing a fast radiatively-driven plume descent and a warming effect on the climate system.

The unexpected radiative impact of the Hunga Tonga eruption of 15th January 2022

WWW.NATURE.COM

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Perturbations to the global climate system changed from net cooling to net heating during the first month after the 2022 Hunga Tonga-Hunga Ha-apai eruption, according to radiative forcing estimates based on...

No one is ignoring that there is a radiative forcing from water vapour but you are conveniently ignoring the 0.36C of warming that is unaccounted for when taking the influence of Hunga Tonga eruption away.

Edited May 8 by Derecho

[WYorksWeather]

 jonboy Well, the only way for certain will be to wait for the effects to mix out of the system. I think Robert Rohde had some stats on the stratospheric H2O content - I'll have to see if the graph has been updated.

[sundog]

Up to 426 ppm co2 levels now.

Record-breaking increase in CO2 levels in Earth’s atmosphere

WWW.IRISHTIMES.COM

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Global average concentration in March was 4.7 parts per million higher than same period last year, researchers find

 

Edited May 9 by sundog

[danm]

Global temperature streak continues with record hot April

NEWS.SKY.COM

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The record heat in April recorded by the EU's Copernicus was blamed on climate change and the lingering impact of the El Nino weather pattern.

 

[matty40s]

⁸Well, the ice - what is was- has finally ended in the Great Lakes, a woeful least ever.

 

[cheeky_monkey]

if you remove global dimming from the equation how much warmer would the world have been 50-100 years ago?