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umsonst.bsky.social
@umsonst.bsky.social
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umsonst.bsky.social
Southern Hemisphere marine heatwave update

Development the last days and same date last year

#climate #earth
Marine heatwaves intensify across the mid latitudes of the Southern Hemisphere the next pictures. Last year in the last picture the Indian Ocean mid-latitudes have a large marine heatwave. A little bit more extreme than last year, till now...
November 25, 2025 at 4:10 PM
umsonst.bsky.social
Southern Hemisphere marine heatwave update

We have now several hot spots developing - would be a bit early to start for real

First 6 days ago, second from yesterday, and the last from last year...

#climate
Marine heatwaves east of Australia, west of South America, and west of South Africa marine heatwaves have formed. 5 days later the marine heatwaves east of Australia, west of South America, and west of South Africa have further intensified. Last year marine heatwaves existed in the Indian Ocean across the mid-latitudes, and east of South America. The Pacific in 2025 a hot spot, had been relatively cool in 2024 - some above average and below average areas.
November 24, 2025 at 4:19 PM
umsonst.bsky.social
In principle all what makes the surface Pacific winds over the tropical Pacific to blow to the east.

And if the energy content in the tropical western Pacific is high enough an El Nino can form.

Its now in El Nino territory while again in the accumulation phase:
November 21, 2025 at 5:25 PM
umsonst.bsky.social
In the Northern Hemisphere tropospheric hight increases the fastest around 30°N - some 150m decade peak... Upper troposphere is warming while the lower stratosphere is cooling
November 21, 2025 at 11:56 AM
umsonst.bsky.social
Southern Hemisphere marine heatwave update

First picture 6 days ago, second 1 day, and the last from 2024, same date

During December they normally start to form

During December they normally start to form. I added a last picture from this year summer 2025-02-04, so you see the problem...
Most the southern Hemisphere oceans are warmer than normal, the warmer regions forming bands around the south poles. The last 5 days not much changed. Last year during the same time it had been similar. The last picture from this year January when large marine heatwaves dominated the Southern Hemisphere ocean.
November 19, 2025 at 8:35 PM
umsonst.bsky.social
Southern Hemisphere marine heatwave update

First is 6 days ago, second from yesterday, and the third from last year.

Currently, they are on track to beat last year - the real intensification should start in December...

#climate #Earth
The first three pictures show the marine heatwave state in the Southern Hemisphere. They develop a circumpolar character. The last one shows the 7 day development. Its in-between with large areas cooling and large ones warming. But the circumpolar above normal SST signal is well developed - but not in the 7 days trend chart. So lets see how it will evolve...
November 14, 2025 at 5:29 PM
umsonst.bsky.social
Next one on the non-linear reaction of currents we are in the process to trigger:

Sea ice loss and stratification will speed up the currents in the Artic (triple) and around Antarctica (60%) in a high warming scenario

#Climate #Earth #Oceans
Shows the Arctic Ocean with weak Eddy field und with a massive energetic eddy field. Here what they write: Abstract Mesoscale horizontal stirring (MHS) is ubiquitous in the oceans, influencing heat and carbon transport, phytoplankton blooms and fish larvae dispersal. The current generation of Earth system models lacks sufficient resolution to properly resolve MHS-relevant small-scale phenomena, such as oceanic mesoscale eddies, leaving it largely unknown how MHS will change in response to greenhouse warming. Here we determine how CO2 doubling and quadrupling will change the surface MHS statistics in Community Earth System Model simulations with 1/10-degree ocean resolution. MHS is analysed using the finite-size Lyapunov exponent, a Lagrangian diagnostic that measures the separation of close trajectories. Projected increases in MHS are expected in the Arctic Ocean and coastal Antarctic regions, driven by enhanced time-mean ocean flow and turbulence which predominantly result from sea ice reduction. https://www.nature.com/articles/s41558-025-02471-2
November 13, 2025 at 8:08 AM
umsonst.bsky.social
We get a non-linear signal in the global current system in the oceans...

upper ocean speeds up, deeper ocean slows down, mainly due to stratification

Now we have the first non-linear signal: eddy kinetic energy in the Kuroshio current intensified by 50% the last decade - Gulf stream 20%

#climate
Map shows where the regions in the oceans are with the most kinetic energy - its where the strong currents exist - east of all continents moving poleward, around Antarctica, and in the equatorial oceans. The Kuroshio current is located east of Japan coming in from the south. Gulf Stream in the Atlantic. Some text excerpts: From the abstract: The Eddy Kinetic Energy (EKE) This study investigates if the global ocean mesoscale variability is becoming more energetic by analyzing 30 years of satellite altimetric observations. We use two observational products: one constructed from a consistent pair of altimeters and another including all available missions. Our results reveal a significant global EKE strengthening of 1–3% per decade. The intensification is concentrated in energetic regions, particularly in the Kuroshio Extension and the Gulf Stream, which show EKE increases of ~ 50% and ~ 20%, respectively, over the last decade. Over the last decade, the EKE in the Kuroshio Extension has increased 6 to 7 times faster than over the last three decades, representing an increase of ~ 50% with respect to mean values. These findings support previous studies that detected an intensification of the Kuroshio Extension, potentially linked to the Pacific Decadal Oscillation. The Gulf Stream is the second region with the largest EKE trends. [...] Over the last decade, this region has increased 8.5 times faster than over the complete altimetric era, representing a statistically significant increase of ~ 20% with respect to mean values. A positive, consistent and increasing EKE trend in the Gulf Stream opens new questions about its relationship with the Atlantic meridional overturning circulation (AMOC) and the subtropical North Atlantic gyre. While over the global oceans the increase in eddy kinetic energy is only about 1-3% per decade EKE in the western boundary currents intensifies much faster. Shows the trend for the global oceans, slowly intensifying and for the eddy rich regions - large currents which intensify much faster. They transport warm water poleward. The Kuroshio EKE increases non-linear, the last decade it went up by staggering 50%... The trend went up by 6-7 fold. In the Gulf Stream its 20% a trend increase by 8.5 fold... The observed strengthening of mesoscale variability in the Gulf Stream challenges existing climate model projections. Our findings emphasize the need for improved representation of small-scale ocean processes in climate models to better understand their influence on the large-scale climate system.
November 12, 2025 at 7:06 PM
umsonst.bsky.social
Southern Hemisphere marine heatwaves update - difference the last 5 days

How intense will be the marine heatwave signal in 2025/26 during summer?
November 9, 2025 at 4:33 PM
umsonst.bsky.social
Next study that we do not have a significant weakening of the AMOC till today

The whole climate system is now collapsing or shifting into a feedback driven state. That is the real story...

And AMOC collapse will have catastrophic effects, but till that happens it won't matter anymore much...
The graph shows AMOC strength modeled which show a gradual decline from out times onward till 2100. RAPID measurement array shows no decline till 2024. Two reanalysis datasets are also show no decline. Here what they write: Observed AMOC exhibits significant variability on timescales ranging from days to decades, masking long-term trends (Figure 1A). Generally, The RAPID array shows that decadal-mean subtropical AMOC exhibited a statistically significant weakening from 2005 to 2014, and virtually no trend since the early 2010s (Figure 1A), probably representing decadal variability rather than ongoing long-term weakening.3 Similarly, the OSNAP array has yet to exhibit any clear trend due to its relatively short observational duration. "Toward an integrated framework on AMOC stability: Combining theory, observations, paleoclimate records, model simulations and AI"; https://www.the-innovation.org/article/doi/10.59717/j.xinn-geo.2025.100167
November 9, 2025 at 12:35 PM
umsonst.bsky.social
We underestimated Southern Ocean outgassing by 40% around Antarctica >40°S

"Substantially underestimated winter CO2 sources of the Southern Ocean"; www.science.org/doi/10.1126/...
Shows three circumpolar bands around Antarctica where net carbon uptake (outer band) and outgassing (middle band 40°S-60°S) happens.
November 7, 2025 at 9:46 PM
umsonst.bsky.social
This one:

For ridge blocks, diabatic heating enhances the upstream wave activity, thus contributing to the persistence of blocks.

"Blocking diversity causes distinct roles of diabatic heating in the Northern Hemisphere"; www.nature.com/articles/s41...
November 7, 2025 at 9:08 PM
umsonst.bsky.social
And this happens while aerosols increase over the SH - this summer will be another important data point - will it further intensify like the last years? If so we are definitely in an extinction level event, as we warmed the oceans way too fast...

And aerosol reduction certainly reinforced it...
November 6, 2025 at 1:01 AM
umsonst.bsky.social
Its a model study while lots of MHW studies and their effects on clouds are observational - with the intensification of MHWs clouds are reduced while weak winds and blocking patterns induce them and strong stratification and shallow upper mixed layer depth precondition the upper ocean for MHWs...
This signal in 2023/24 had not been aerosols and their effect on clouds but a feedback between the upper ocean and atmosphere suddenly going off charts also driven by the SST pattern effect on cloud cover...
November 6, 2025 at 12:52 AM
umsonst.bsky.social
As cooling the planet via re-greening gains attraction here some important key publications on this issue - graph study...

#climate #Earth
Pictures show the affect of vegetation from the local to the global on circulation in four steps of scale. The abstract of the most recent review: Vegetation often understood merely as the result of long-term climate conditions. However, vegetation itself plays a fundamental role in shaping Earth's climate by regulating the energy, water, and biogeochemical cycles across terrestrial landscapes. It exerts influence by altering surface roughness, consuming significant water resources through transpiration and interception, lowering atmospheric CO2 concentration, and controlling net radiation and its partitioning into sensible and latent heat fluxes. This influence propagates through the atmosphere, from microclimate scales to the entire atmospheric boundary layer, subsequently impacting large-scale circulation and the global transport of heat and moisture. Understanding the feedbacks between vegetation and atmosphere across multiple scales is crucial for predicting the influence of land use and cover changes and for accurately representing these processes in climate models. This short review aims to discuss the mechanisms through which vegetation modulates climate across spatial and temporal scales. Particularly, we evaluate the influence of vegetation on circulation patterns, precipitation and temperature, both in terms of trends and extreme events, such as droughts and heatwaves. The main goal is to highlight the state of science and review recent studies that may help advance our collective understanding of vegetation feedbacks and the role they play in climate. Vegetation-climate feedbacks across scales"; https://arxiv.org/abs/2409.04872 Shows how forests help to bring water more inland - the animate precipitation, evaporate it and thereby help to transport it more inland. "Trees, forests and water: Cool insights for a hot world"; https://www.sciencedirect.com/science/article/pii/S0959378017300134 Shows a map of global vegetation cover and water risk - where it is high there is lower drought and water risk. "Managing Forests for Both Downstream and Downwind Water"; https://www.frontiersin.org/journals/forests-and-global-change/articles/10.3389/ffgc.2019.00064/full
November 5, 2025 at 7:55 PM
umsonst.bsky.social
Just went a little bit through the literature I did not know and found this passage - so it could be shallower than in the picture.

Actually this is what I remember gas hydrates can be quite shallow in the Arctic self regions where once glaciers existed...
Unlike results from the synthetic seismic data (Figure 5), we did not identify reflections indicating the top of gas hydrates either intra-permafrost or sub-permafrost. Possible reasons are insufficient impedance contrasts for intra-permafrost gas hydrates and sub-permafrost gas hydrate thicknesses that are smaller than the seismicresolution. For example, gas hydrate zones at the Mallik gas hydrate field on Richards Island on the coast ofthe Beaufort Sea (Figure 1) show thicknesses between 37 and 51 m (Dallimore & Collett, 2005). There, zone B(51 m thick) consists of a “series of 5–10 m thick gas hydrate-bearing sand units separated by 0.5–1 m thick gashydrate-free silt layers,” which possess heterogeneous gas hydrate saturations. A seismic response from such gashydrate-composed layers may not be explicit, particularly with our seismic resolution of c. 17–23 m (λ/4: 28 Hz;2,000–2,600 m/s). H "Revealing the Extent of Submarine Permafrost and Gas Hydrates in the Canadian Arctic Beaufort Sea Using Seismic Reflection Indicators"; https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023GC010884
November 4, 2025 at 6:38 PM
umsonst.bsky.social
But as there exist always a but - while one seems not as bad as feared there exist a real kicker in the system :D

Could be intensifying groundwater channels opening up UNDER the ESAS - question: is this shit new or old? This study things old...

www.pnas.org/doi/full/10....
November 4, 2025 at 5:51 PM
umsonst.bsky.social
Here the observations from some studies - could it be that oxygen saturation are a good proxy for AMOC strength?
November 4, 2025 at 12:56 PM
umsonst.bsky.social
Question on fig. 5 The oxygen saturation signal. It went up down to 1000m depth. Is it due to enhanced vertical mixing towards the end of the time line increasing?

In 2012-2016 we had the largest freshwater influx and a restrengthening signal of the AMOC towards 2017

Do you have an interpretation?
November 4, 2025 at 12:55 PM
umsonst.bsky.social
How can models simulate the warming of a chaotic getting feedback system if they can not even do it for an undisturbed state?

The spread is some 1.5°C above and below mean warming levels...
But hey, do not do one thing: evaluate the models ability to simulate the feedbacks on their ability to simulate the mean feedback state of a undisturbed state. Its the most prominent case of ignoring physics as the interplay of all systems constitutes the mean temperature. Anyhow how could there exist a physical problem with models if they can not simulate historic mean temperatures??? Morons who think so...
November 3, 2025 at 5:00 PM
umsonst.bsky.social
AMOC decline from a subsequent study on Atlantic heat content build up

This time a significant weakening

The AMOC discussion is a big fuck up with two opposing camps

Equatorial Atlantic mid-depth warming indicates Atlantic meridional overturning circulation slowdown www.nature.com/articles/s43...
This study on AMOC decline using also as a proxy Atlantic heat content changes sees a significant weakening starting in the 90s. while the previous I posted from July does not sees it. In my opinion the whole AMOC study discussion is a big fuck up! Its a heavily biased discussion with two camps: one it has already weakened while the other it has not significantly weakened till now - the later is a result of direct measurements showing no weakening... So lets see if the weakening really will start now... I'm 70/30 for another increase in warm water transport northward driven by intensifying and more northward moving storms in the NA and then a weakening or we get now a signal...
November 1, 2025 at 10:33 PM
umsonst.bsky.social
As there exist so much fuss about a substantially weakened AMOC here another one:

"The observed heat storage indicates an overall AMOC slowdown by only 1.31 ± 0.39 Sv since the 1950s. Considering the pronounced natural variability, this weak anthropogenic AMOC slowdown probably has not emerged yet"
Graphs shows AMOC strength declined somewhat in observations but only weakly. Still things can become interesting up there in the North Atlantic. Here the study: "Heat Storage Pattern Linked to the Atlantic Meridional Overturning Circulation Slowdown"; https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GL116801 Shows warming patterns across the North Atlantic basin. What is interesting and important that the global oceans channel heat into the Atlantic. This is the reason it gains heat much faster than any other great basin. Important: the whole basins upper water column is warming, especially the first 700m. This picture shows the upper water transport from the Indian and Southern Ocean into the Atlantic basin from the South. The circumpolar winds strengthened driving the speed of the subtropical gyres in the South Atlantic and in the Indian Ocean basin which increased the warm water transport into the Atlantic Basin. Most seems to come from the Indian Ocean, but I'm not up to date as this study was from 2011 - want to check how that still holds but could be possible as in 2024 massive amounts of heat had been channeled into the Atlantic which gained a massive amount of heat - should have come from the western Pacific which gained massive amounts of heat prior to the El Nino in 2023...
November 1, 2025 at 10:17 PM
umsonst.bsky.social
Just this one shows how fast the Amazon could go up in flames - if this happens already what will happen along the way or after we reached 2°C of mean warming?

This thing can make puff and whoosh...

Also amplification between drought and tropical Atlantic SSTs is now discussed by a new preprint...
November 1, 2025 at 7:47 PM
umsonst.bsky.social
Not too much of a decline - here the table: psl.noaa.gov/cgi-bin/data...
November 1, 2025 at 7:20 PM
umsonst.bsky.social
@zohrankmamdani.bsky.social‬ - this one is also highly important to understand: you have a heat buildup in the Northwestern Atlantic right off New York...

"Recent warming and decadal variability of Gulf of Maine and Slope Water"; aslopubs.onlinelibrary.wiley.com/doi/10.1002/...
October 31, 2025 at 7:38 PM