New Research

[Gowon]

Earth’s fiery interior is ‘swallowing up’ more carbon than thought

WWW.MSN.COM

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Scientists previously believed carbon subducted into the Earth’s mantle largely re-emerged through volcanoes

 

[Gowon]

On 16/07/2021 at 10:44, Gray-Wolf said:

I take it the German (and others) flooding will see the same 'rapid attribution' of the events there?

The majority of folks are paving over their gardens and then wonder why there's a flood every time we have a torrential downpour.. It wouldn't happen so often if some of the rain water had a chance to soak into the ground.

[knocker]

Tropical teleconnection impacts on Antarctic...

WWW.NATURE.COM

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Nature Reviews Earth & Environment - Tropical teleconnections can influence polar climates through the generation of stationary Rossby waves. This Review outlines the dynamics and impacts of...

 

[Methuselah]

When I first saw this story I though it was a joke. Apparently not!

Cows ‘potty-trained’ in experiment to reduce greenhouse gas emissions | Climate crisis | The Guardian

WWW.THEGUARDIAN.COM

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Calves were taught to use a barn’s toilet area with rewards and mild punishments, significantly limiting ammonia release

 

[Methuselah]

An interesting presentation:

 

[knocker]

Projections of northern hemisphere extratropical climate underestimate internal variability and associated uncertainty

Abstract

Internal climate variability will play a major role in determining change on regional scales under global warming. In the extratropics, large-scale atmospheric circulation is responsible for much of observed regional climate variability, from seasonal to multidecadal timescales. However, the extratropical circulation variability on multidecadal timescales is systematically weaker in coupled climate models. Here we show that projections of future extratropical climate from coupled model simulations significantly underestimate the projected uncertainty range originating from large-scale atmospheric circulation variability. Using observational datasets and large ensembles of coupled climate models, we produce synthetic ensemble projections constrained to have variability consistent with the large-scale atmospheric circulation in observations. Compared to the raw model projections, the synthetic observationally-constrained projections exhibit an increased uncertainty in projected 21st century temperature and precipitation changes across much of the Northern extratropics. This increased uncertainty is also associated with an increase of the projected occurrence of future extreme seasons.

https://www.nature.com/articles/s43247-021-00268-7

[knocker]

Climate change research and action must look beyond 2100

Abstract

Anthropogenic activity is changing Earth's climate and ecosystems in ways that are potentially dangerous and disruptive to humans. Greenhouse gas concentrations in the atmosphere continue to rise, ensuring that these changes will be felt for centuries beyond 2100, the current benchmark for projection. Estimating the effects of past, current, and potential future emissions to only 2100 is therefore short-sighted. Critical problems for food production and climate-forced human migration are projected to arise well before 2100, raising questions regarding the habitability of some regions of the Earth after the turn of the century. To highlight the need for more distant horizon scanning, we model climate change to 2500 under a suite of emission scenarios and quantify associated projections of crop viability and heat stress. Together, our projections show global climate impacts increase significantly after 2100 without rapid mitigation. As a result, we argue that projections of climate and its effects on human well-being and associated governance and policy must be framed beyond 2100.

https://onlinelibrary.wiley.com/doi/10.1111/gcb.15871

[knocker]

Decadal climate variability in the tropical Pacific: Characteristics, causes, predictability, and prospects

A decades-long affair

Decadal climate variability and change affects nearly every aspect of our world, including weather, agriculture, ecosystems, and the economy. Predicting its expression is thus of critical importance on multiple fronts. Power et al. review what is known about tropical Pacific decadal climate variability and change, the degree to which it can be simulated and predicted, and how we might improve our understanding of it. More accurate projections will require longer and more detailed instrumental and paleoclimate records, improved climate models, and better data assimilation methods. —HJS

https://www.science.org/doi/10.1126/science.aay9165#.YVaJ4kwGbeE.twitter

[knocker]

Increasing heat and rainfall extremes now far outside the historical climate

Abstract

Over the last decade, the world warmed by 0.25 °C, in-line with the roughly linear trend since the 1970s. Here we present updated analyses showing that this seemingly small shift has led to the emergence of heat extremes that would be virtually impossible without anthropogenic global warming. Also, record rainfall extremes have continued to increase worldwide and, on average, 1 in 4 rainfall records in the last decade can be attributed to climate change. Tropical regions, comprised of vulnerable countries that typically contributed least to anthropogenic climate change, continue to see the strongest increase in extremes.

https://www.nature.com/articles/s41612-021-00202-w

[knocker]

Distinct tropospheric and stratospheric mechanisms linking historical Barents-Kara sea-ice loss and late winter Eurasian temperature variability

James Screen

Two main pathways have been proposed through which Arctic sea-ice loss could cause colder winters over Eurasia. Our paper out this week sought to quantify the so-called tropospheric and stratospheric pathways. Spoiler alert: they contribute roughly equally

Abstract

Reduced Arctic sea-ice has been proposed to induce severe Eurasian cold events. However, the physical mechanisms for this connection, particularly the relative importance of tropospheric and stratospheric processes, remain unclear. Using ERA-Interim reanalysis data and WACCM-SC simulations, we show that the Eurasian cooling induced by reduced sea-ice centers over eastern Asia and northern Europe. Tropospheric and stratospheric processes contribute roughly equally to the cooling over eastern Asia, while the stratospheric and tropospheric contributions are 60% and 40%, respectively, over northern Europe. In the tropospheric pathway, weakened meridional temperature gradient due to reduced sea-ice strengthens the Ural blocking and enhances the Siberian High. The enhanced Siberian High favors two streams of cold air-mass, reaching northern Europe and eastern Asia. In the stratospheric pathway, enhanced upward-propagating planetary wave 1 causes a shift of the stratospheric polar vortex towards Eurasia and consequently, tropospheric cyclonic anomalies are induced that enhance surface cold anomalies.

Plain Language Summary

Recent years of below-average Arctic sea-ice have been proposed to be linked to severe cold winters over Eurasia. However, the causality and mechansims of this connection are unclear. Two general pathways have been proposed through which reduced sea-ice could induce cold winter, namely, the tropospheric and stratospheric pathways. Here, we sought to measure the relative importance of stratospheric and tropospheric processes in this connection. Using observations and model simulations, we find that distinct tropospheric and stratospheric mechanisms contribute roughly equally to the Eurasian winter cooling in response to reduced sea-ice. In the tropospheric pathway, we find that the Siberian High, an important surface high pressure system for Eurasian winter climate, is enhanced by the reduced Arctic sea-ice. This favors the intrusion of cold polar air-mass into Eurasia. In the stratospheric pathway, the stratospheric polar vortex, a strong wintertime circumpolar westerly system (∼15-40 km), is shifted towards Eurasia by the reduced sea-ice, which also favors the cold anomalies over Euraisa.

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2021GL095262

[knocker]

The oldest, thickest, and toughest Arctic sea ice is weakening.

Arctic sea ice has starkly declined over the last 40 years, though polar scientists believed a region dubbed the "Last Ice Area" was largely resistant to melting as the planet warmed. Yet new research published in the scientific journal Geophysical Research Letters shows a hole nearly the size of Rhode Island opened up there in 2020, meaning even places with robust ice some 15-feet thick (or more) is increasingly susceptible in today's warming climate.

https://mashable.com/article/arctic-climate-change

[knocker]

Clean energy could save American lives to tune of $700 billion per year

New research quantifies how actions to curb climate change will yield immediate benefits from cleaner air, better health, and longer lives.

The case for climate solutions has long been hindered because of the decades it will take for investments made today to yield benefits in the form of less extreme weather impacts. Carbon dioxide pollution remains in the atmosphere for upwards of a millennium, and so efforts to curb carbon emissions will only slowly bend the global warming curve. Clean technologies deployed today will yield significant changes in extreme weather only toward the middle of the century.

Compelling people to support climate solutions thus usually requires appealing to their better natures; to invest in protecting the future quality of life of today’s children. People often have difficulty making decisions based on such long-term considerations.

But as a new study in the Proceedings of the National Academy of Sciences (PNAS) concludes, curbing climate change does yield immediate benefits in the form of cleaner air resulting in healthier and longer lives. The paper was authored by 11 scientists from Duke and Columbia Universities and the NASA Goddard Institute for Space Studies (GISS), including lead author Drew Shindell, who has published over 250 peer-reviewed climate studies over the past 25 years, and NASA GISS Director Gavin Schmidt.

https://yaleclimateconnections.org/2021/11/clean-energy-could-save-american-lives-to-tune-of-700-billion-per-year/

[knocker]

Global CO2 emissions have been flat for a decade, new data reveals

Global carbon dioxide (CO2) emissions from fossil fuels and cement have rebounded by 4.6% this year, new estimates suggest, following a Covid-related dip of 5.2% in 2020.

The Global Carbon Project (GCP) projects that fossil emissions in 2021 will reach 36.4bn tonnes of CO2 (GtCO2), only 0.8% below their pre-pandemic high of 36.7GtCO2 in 2019.

The researchers say they “were expecting some sort of rebound in 2021” as the global economy bounced back from Covid-19, but that it was “bigger than expected”.

While fossil emissions are expected to return to near-record levels, the study also reassesses historical emissions from land-use change, revealing that global CO2 output overall may have been effectively flat over the past decade.

The 2021 GCP almost halves the estimate of net emissions from land-use change over the past two years – and by an average of 25% over the past decade.

These changes come from an update to underlying land-use datasets that lower estimates of cropland expansion, particularly in tropical regions. Emissions from land-use change in the new GCP dataset have been decreasing by around 4% per year over the past decade, compared to an increase of 1.8% per year in the prior version. 

However, the GCP authors caution that uncertainties in land-use change emissions remain large and “this trend remains to be confirmed”.

https://www.carbonbrief.org/global-co2-emissions-have-been-flat-for-a-decade-new-data-reveals

[knocker]

Interannual variability of the frequency of MJO phases and its association with two types of ENSO

Abstract

In this study, we reexamine the effect of two types of El Niño Southern Oscillation (ENSO) modes on Madden Julian Oscillation (MJO) activity in terms of the frequency of MJO phases. Evaluating all-season data, we identify two dominant zonal patterns of MJO frequency exhibiting prominent interannual variability. These patterns are structurally similar to the Wheeler and Hendon (Mon. Weather Rev. 132:1917–1932, 2004) RMM1 and RMM2 spatial patterns. The first pattern explains a higher frequency of MJO activity over the Maritime Continent and a lower frequency over the central Pacific Ocean and the western Indian Ocean, or vice versa. The second pattern is associated with a higher frequency of MJO active days over the eastern Indian Ocean and a lower frequency over the western Pacific, or vice versa. We find that these two types of MJO frequency patterns are related to the central Pacific and eastern Pacific ENSO modes. From the positive to the negative ENSO (central Pacific or eastern Pacific) phases, the respective MJO frequency patterns change their sign. The MJO frequency patterns are the lag response of the underlying ocean state. The coupling between ocean and atmosphere is exceedingly complex. The first MJO frequency pattern is most prominent during the negative central-Pacific (CP-type) ENSO phases (specifically during September–November and December-February seasons). The second MJO frequency pattern is most evident during the positive eastern-Pacific (EP-type) ENSO phases (specifically during March–May, June–August and September–November). Different zonal circulation patterns during CP-type and EP-type ENSO phases alter the mean moisture distribution throughout the tropics. The horizontal convergence of mean background moisture through intraseasonal winds are responsible for the MJO frequency anomalies during the two types of ENSO phases. The results here show how the MJO activity gets modulated on a regional scale in the presence of two types of ENSO events and can be useful in anticipating the seasonal MJO conditions from a predicted ENSO state.

https://www.nature.com/articles/s41598-021-91060-2

[jonboy]

3 hours ago, knocker said:

Global CO2 emissions have been flat for a decade, new data reveals

Global carbon dioxide (CO2) emissions from fossil fuels and cement have rebounded by 4.6% this year, new estimates suggest, following a Covid-related dip of 5.2% in 2020.

The Global Carbon Project (GCP) projects that fossil emissions in 2021 will reach 36.4bn tonnes of CO2 (GtCO2), only 0.8% below their pre-pandemic high of 36.7GtCO2 in 2019.

The researchers say they “were expecting some sort of rebound in 2021” as the global economy bounced back from Covid-19, but that it was “bigger than expected”.

While fossil emissions are expected to return to near-record levels, the study also reassesses historical emissions from land-use change, revealing that global CO2 output overall may have been effectively flat over the past decade.

The 2021 GCP almost halves the estimate of net emissions from land-use change over the past two years – and by an average of 25% over the past decade.

These changes come from an update to underlying land-use datasets that lower estimates of cropland expansion, particularly in tropical regions. Emissions from land-use change in the new GCP dataset have been decreasing by around 4% per year over the past decade, compared to an increase of 1.8% per year in the prior version. 

However, the GCP authors caution that uncertainties in land-use change emissions remain large and “this trend remains to be confirmed”.

https://www.carbonbrief.org/global-co2-emissions-have-been-flat-for-a-decade-new-data-reveals

So given the reports findings that CO2 emmissions have been flat for the last 10 years what drives temperature? Or have temperature stabalised too and potentually set to fall?

[Methuselah]

12 minutes ago, jonboy said:

So given the reports findings that CO2 emmissions have been flat for the last 10 years what drives temperature? Or have temperature stabalised too and potentually set to fall?

But it's only emissions that have stabilised, @jonboy. The amount of CO2 in the atmosphere is still increasing?

[jonboy]

7 minutes ago, Ed Stone said:

But it's only emissions that have stabilised, @jonboy. The amount of CO2 in the atmosphere is still increasing?

so if emmissions are flat where is the increase coming from?

[Methuselah]

1 minute ago, jonboy said:

so if emmissions are flat where is the increase coming from?

Because the input is still exceeding the output: It is a bit like filling a bath with the plug only halfway in, in that so long as there's more water coming from the tap than what can escape down the plughole, the water level will continue to rise. To make the level fall, you'd need to either open the plug or turn down the tap. Or both?

I hope that that makes sense!

[knocker]

It does Pete. I was just about to post that they are flat, not gone, so CO2 is still being added and with the long lifetime..................

[knocker]

Climate change in the geological record

The geological record captures multiple episodes of climate change. Dan Lunt and colleagues report on the use of past climate-change reconstructions and modelling to better understand the dynamics of the climate system and the range of possible impacts under current warming

https://geoscientist.online/sections/unearthed/climate-change-in-the-geological-record/

[knocker]

From Atmospheric Waves to Heatwaves: A Waveguide Perspective for Understanding and Predicting Concurrent, Persistent and Extreme Extratropical Weather

Abstract

A notable number of high impact weather extremes have occurred in recent years, often associated with persistent, strongly meandering atmospheric circulation patterns known as Rossby waves. Because of the high societal and ecosystem impacts, it is of great interest to be able to accurately project how such extreme events will change with climate change, and to predict these events on seasonal to subseasonal (S2S) timescales. There are multiple physical links connecting upper atmosphere circulation patterns to surface weather extremes, and it is asking a lot of our dynamical models to accurately simulate all of these. Subsequently, our confidence in future projections and S2S forecasts of extreme events connected to Rossby waves remains relatively low. We also lack full fundamental theories for the growth and propagation of Rossby waves on the spatial and temporal scales relevant to extreme events, particularly under strongly non-linear conditions. By focussing on one of the first links in the chain from upper atmospheric conditions to surface extremes -- the Rossby waveguide -- it may be possible to circumvent some model biases in later links. To further our understanding of the nature of waveguides, links to persistent surface weather events and their representation in models, we recommend: exploring these links in model hierarchies of increasing complexity, developing fundamental theory, exploiting novel large ensemble data sets, harnessing deep learning, and increased community collaboration. This would help increase understanding and confidence in both S2S predictions of extremes and of projections of the impact of climate change on extreme weather events.

https://journals.ametsoc.org/view/journals/bams/aop/BAMS-D-21-0170.1/BAMS-D-21-0170.1.xml

[knocker]

One billion face heat-stress risk from 2°C rise

The numbers of people in regions across the world affected by extreme heat stress – a potentially fatal combination of heat and humidity – could increase nearly 15-fold if the world’s temperature rise reaches 2°C.

https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2021/2c-rise-to-put-one-in-eight-of-global-population-at-heat-stress-risk

[knocker]

According to Dr Zeke Hausfather this paper is a really big deal; it represents a fundamental reassessment of our understanding of climate change over the past 20,000 years. It now seems much clearer current warming is unprecedented since at least before the last ice age. Unfortunately it's behind a paywall

Globally resolved surface temperatures since the Last Glacial Maximum

Abstract

Climate changes across the past 24,000 years provide key insights into Earth system responses to external forcing. Climate model simulations1,2 and proxy data3,4,5,6,7,8 have independently allowed for study of this crucial interval; however, they have at times yielded disparate conclusions. Here, we leverage both types of information using paleoclimate data assimilation9,10 to produce the first proxy-constrained, full-field reanalysis of surface temperature change spanning the Last Glacial Maximum to present at 200-year resolution. We demonstrate that temperature variability across the past 24 thousand years was linked to two primary climatic mechanisms: radiative forcing from ice sheets and greenhouse gases; and a superposition of changes in the ocean overturning circulation and seasonal insolation. In contrast with previous proxy-based reconstructions6,7 our results show that global mean temperature has slightly but steadily warmed, by ~0.5 °C, since the early Holocene (around 9 thousand years ago). When compared with recent temperature changes11, our reanalysis indicates that both the rate and magnitude of modern warming are unusual relative to the changes of the past 24 thousand years.

https://www.nature.com/articles/s41586-021-03984-4

[Gowon]

Carbon dioxide: Scientists show how to turn it back to coal

WWW.MSN.COM

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Dr Torben Daeneke and Dr Dorna Esrafilzadeh from RMIT University show how to turn carbon dioxide back into solid coal. Dr Daeneke says "We can turn it back into coal and bury beneath the ground."