Showing posts with label trend. Show all posts
Showing posts with label trend. Show all posts

Friday, January 15, 2021

2020: Hottest Year On Record

NASA data show that 2020 was the hottest year on record.



The image below shows that high temperature in 2020 hit Siberia and the Arctic Ocean.

In above images, the temperature anomaly is compared to 1951-1980, NASA's default baseline. When using an earlier baseline, the data need to be adjusted. The image below shows a trendline pointing at an 0.31°C adjustment for a 1900 baseline. 



Additional adjustment is needed when using a 1750 baseline, while it also makes sense to add further adjustment for higher polar anomalies and for air temperatures over oceans, rather than sea surface water temperatures. In total, a 0.78°C adjustment seems appropriate, as has been applied before, such as in this analysis. For the year 2020, this translates in a temperature rise of 1.8029°C versus the year 1750.

Three trends: blue, purple and red

Will the global temperature rise to 3°C above 1750 by 2026? The blue trend below is based on 1880-2020 NASA Land+Ocean data and adjusted by 0.78°C to reflect a 1750 baseline, ocean air temperatures and higher polar anomalies, and it crosses a 3°C rise in 2026.



The trend shows a temperature for 2020 that is slightly higher than indicated by the data. This is in line with the fact that we're currently in a La Niña period and that we're also at a low point in the sunspot cycle, as discussed in an earlier post. The blue trend also shows that the 1.5°C treshold was already crossed even before the Paris Agreement was accepted. 



The second (purple) trend is based on a shorter period, i.e. 2006-2020 NASA land+ocean (LOTI) data, again adjusted by 0.78°C to reflect a 1750 baseline, ocean air temperatures and higher polar anomalies. The trend approaches 10°C above 1750 by 2026. The trend is based on 15 years of data, making it span a 30-year period centered around end 2020 when extended into the future for a similar 15 year period. The trend approaches 10°C above 1750 in 2026.

The trend is displayed on the backdrop of an image from an earlier post, showing how a 10°C rise could eventuate by 2026 when adding up the impact of warming elements and their interaction.



The stacked bars are somewhat higher than the trend. Keep in mind that the stacked bars are for the month February, when anomalies can be significantly higher than the annual average.

Temperature rise for February 2016 versus 1900.
In the NASA image on the right, the February 2016 temperature was 1.70°C above 1900 (i.e. 1885-1914). In the stacked-bar analysis, the February 2016 rise from 1900 was conservately given a value of 1.62°C, which was extended into the future, while an additional 0.3°C was added for temperature rise from pre-industrial to 1900.

Later analyses such as this one also added a further 0.2°C to the temperature rise, to reflect ocean air temperatures (rather than water temperatures) and higher polar anomalies (note the grey areas on the image in the right).

Anyway, the image shows two types of analysis on top of each other, one analysis based on trend analysis and another analysis based on a midel using high values for the various warming elements. The stacked-bar analysis actually doesn't reflect the worst-case scenario, an even faster rise is illustrated by the next trend, the red line.

The third (red) trend suggests that we may have crossed the 2°C treshold in the year 2020. The trend is based on a recent period (2009-2020) of the NASA land+ocean data, again adjusted by 0.78°C to reflect a 1750 baseline, ocean air temperatures and higher polar anomalies.




Where do we go from here? 

It's important to acknowledge the danger of acceleration of the temperature rise over the next few years. The threat is illustrated by the image below and shows upmost prominently in the red trend. 


Of the three trends, the red trend is based on the shortest period, and it does indicate that we have aready crossed the 2°C treshold and we could be facing an even steeper temperature rise over the next few years.

We're in a La Niña period and we're also at a low point in the sunspot cycle. This suppresses the temperature somewhat, so the 2020 temperature should actually be adjusted upward to compensate for such variables. Importantly, while such variables do show up more when basing trends on shorter periods, the data have not be adjusted for this in this case, so the situation could actually be even worse. 

At a 3°C rise, humans will likely go extinct, while most life on Earth will disappear with a 5°C rise, and as the temperature keeps rising, oceans will evaporate and Earth will go the same way as Venus, a 2019 analysis warned. 

Dangerous acceleration of the temperature rise 

There are many potential causes behind the acceleration of the temperature rise, such as the fact that the strongest impact of carbon dioxide is felt ten years after emission, so we are yet to experience the full wrath of the carbon dioxide emitted over the past decade. However, this doesn't explain why 2020 turned out to be the hottest year on record, as opposed to - say - 2019, given that in 2020 carbon dioxide emissions were 7% lower than in 2019.

James Hansen confirms that the temperature rise is accelerating, and he points at aerosols as the cause. However, most cooling aerosols come from industries such as smelters and coal-fired power plants that have hardly reduced their operations in 2020, as illustrated by the image below, from the aerosols page


Above image shows that on December 17, 2020, at 10:00 UTC, sulfate aerosols (SO₄) were as high as 6.396 τ at the green circle. Wind on the image is measured at 850 hPa.

Could the land sink be decreasing? A recent study shows that the mean temperature of the warmest quarter (3-month period) passed the thermal maximum for photosynthesis during the past decade. At higher temperatures, respiration rates continue to rise in contrast to sharply declining rates of photosynthesis. Under business-as-usual emissions, this divergence elicits a near halving of the land sink strength by as early as 2040. While this is a frightening prospect, it still doesn't explain why 2020 turned out to be the hottest year on record. 

Oceans are taking up less heat, thus leaving more heat in the atmosphere. The danger is illustrated by the image below. 


The white band around -60° (South) indicates that the Southern Ocean has not yet caught up with global warming, featuring low-level clouds that reflect sunlight back into space. Over time, the low clouds will decrease, which will allow more sunlight to be absorbed by Earth and give the world additional warming. A recent study finds that, after this 'pattern effect' is accounted for, committed global warming at present-day forcing rises by 0.7°C. While this is very worrying, it still doesn't explain why 2020 turned out to be the hottest year on record. 

Ocean stratification contributes to further surface warming, concludes another recent study
"The stronger ocean warming within upper layers versus deep water has caused an increase of ocean stratification in the past half century. With increased stratification, heat from climate warming less effectively penetrates into the deep ocean, which contributes to further surface warming. It also reduces the capability of the ocean to store carbon, exacerbating global surface warming. Furthermore, climate warming prevents the vertical exchanges of nutrients and oxygen, thus impacting the food supply of whole marine ecosystems."
"By uptaking ~90% of anthropogenic heat and ~30% of the carbon emissions, the ocean buffers global warming. [The] ocean has already absorbed an immense amount of heat, and will continue to absorb excess energy in the Earth’s system until atmospheric carbon levels are significantly lowered. In other words, the excess heat already in the ocean, and heat likely to enter the ocean in the coming years, will continue to affect weather patterns, sea level, and ocean biota for some time, even under zero carbon emission conditions."
Many feedbacks are starting to kick in with greater ferocity, with tipping points threatening to get crossed or already crossed, such as the latent heat tipping point, i.e. loss of the ocean heat buffer, as Arctic sea ice keeps getting thinner. As the above map also shows, the temperature rise is hitting the Arctic Ocean particularly hard. At least ten tipping points are affecting the Arctic, including the latent heat tipping point and the methane hydrates tipping point, as illustrated by the image below.
 
[ from an earlier post ]

A combination of higher temperatures and the resulting feedbacks such as stronger ocean stratification, stronger wind, decline of Arctic snow and ice and a distorted Jet Stream is threatening to cause formation of a lid at the surface of the North Atlantic Ocean that enables more heat to move to the Arctic Ocean. This could cause huge amounts of methane to erupt from the seafloor, thus contributing to cause the 1,200 ppm CO₂e cloud tipping point to get crossed, resulting in an extra 8°C rise, as an earlier post and a recent post warned.

Dangerous acceleration of the temperature rise

The danger is that methane is erupting in the Arctic from the seafloor and that this increasingly contributes to methane reaching the stratosphere. 

While methane initially is very potent in heating up the atmosphere, it is generally broken down relatively quickly, but in the atmosphere over the Arctic, there is very little hydroxyl to break down the methane. 

Methane also persists much longer in the stratosphere, which contributes to its accumulation there. 


Large amounts of methane may already be erupting from the seafloor of the Arctic Ocean, rising rapidly and even reaching the stratosphere

This danger is getting little public attention. The NOAA image on the right shows the globally-averaged, monthly mean atmospheric methane abundance derived from measurements from marine surface sites. Measurements that are taken at sea level do not reflect methane very well that is rising up from the seafloor of the Arctic Ocean, especially where the methane rises up high in plumes. 

Satellite measurements better reflect the danger. The image on the right shows that the MetOp-1 satellite recorded peak methane levels as high as 2715 ppb at 469 mb on the morning of January 6, 2021. 

Most of the high (magenta-colored) levels of methane are located over oceans and a lot of them over the Arctic Ocean. 

The next image on the right shows the situation closer to sea level, at 586 mb, where even less of the high levels of methane show up over land, indicating that the methane originated from the seafloor. 

The third image on the righ shows the situation even closer to sea level, at 742 mb, and almost all high levels of methane show up over the Arctic Ocean and over areas where the Atlantic Ocean and the Pacific Ocean border on the Arctic. 

Because methane is lighter than air and much lighter than water, methane erupting from the seafloor will quickly rise up vertically. While much of the methane that is released from the seabed can get broken down in the water by microbes, methane that is rising rapidly and highly concentrated in the form of plumes will leave little opportunity for microbes to break it down in the water column, especially where waters are shallow,
as is the case in much of the Arctic Ocean.

As methane hydrates destabilize, methane will erupt with an explosive force, since methane is highly compressed inside the hydrate (1 m³ of methane hydrate can release 160 m³ of gas). Such eruptions can destabilize further hydrates located nearby. Because of this explosive force, plumes of methane can rise at high speed through the water column. 

Because methane is so much lighter than water, large methane releases from the seafloor will form larger bubbles that merge and stick together, developing more thrust as they rise through the water.

Because of this thrust, methane plumes will keep rising rapidly after entering the atmosphere, and the plumes will more easily push away aerosols and gases that slow down the rise in the air of methane elsewhere, such as where methane is emitted by cows. 

A further image of another satellite is added on the right. The N2O satellite recorded methane levels as high as 2817 ppb at 487 mb on the morning of January 10, 2021. 

Such sudden and very high peaks can hardly be caused by agriculture or wetlands, but instead they are likely caused by destabilization of methane hydrates in sediments at the seafloor. 

Further contributing to the danger is the fact that little hydroxyl is present in the atmosphere over the Arctic, so it is much harder for this methane to get broken down in the air over the Arctic, compared to methane emissions elsewhere. 

Finally, the edge of the stratosphere is much lower over the Arctic, as discussed in an earlier post.

All this makes that methane that is erupting from the seafloor of the Arctic Ocean is more prone to accumulate in the stratosphere. Once methane is in the stratosphere, it's unlikely that it will come back into the troposphere.

The IPCC AR5 (2013) gave methane a lifetime of 12.4 years. The IPCC TAR (2001) gave stratospheric methane a lifetime of 120 years, adding that less than 7% of methane did reach the stratosphere at the time. According to IPCC AR5, of the methane that gets broken down by hydroxyl in the atmosphere, some 8.5% got broken down in the stratosphere.

Conclusions

The situation is dire and calls for immediate, comprehensive and effective action as described in the Climate Plan.

In the video below, Paul Beckwith discusses the situation: 


For another perspective, Guy McPherson discusses the situation in the video below, Edge of Extinction: Maybe I’m Wrong





Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• NASA Global Land-Ocean Temperature Index
https://data.giss.nasa.gov/gistemp

• What are El Niño and La Niña?
https://oceanservice.noaa.gov/facts/ninonina.html

• Multivariate El Niño/Southern Oscillation (ENSO) Index Version 2 (MEI.v2)
https://psl.noaa.gov/enso/mei 
 
• Temperatures keep rising
https://arctic-news.blogspot.com/2020/12/temperatures-keep-rising.html

• There is no time to lose
https://arctic-news.blogspot.com/2020/11/there-is-no-time-to-lose.html

• Possible climate transitions from breakup of stratocumulus decks under greenhouse warming, by Tapio Schneider et al. (2019)
https://www.nature.com/articles/s41561-019-0310-1

• A rise of 18°C or 32.4°F by 2026?

• Greater committed warming after accounting for the pattern effect - by Chen Zhou et al. 

• Upper Ocean Temperatures Hit Record High in 2020 - by Lijing Cheng et al. 
https://link.springer.com/article/10.1007/s00376-021-0447-x

• How close are we to the temperature tipping point of the terrestrial biosphere? - by Katharyn Duffy et al.
https://advances.sciencemag.org/content/7/3/eaay1052

• Methane hydrates tipping point threatens to get crossed

• Cold freshwater lid on North Atlantic

• Aerosols

• NOAA - Trends in Atmospheric Methane
https://www.esrl.noaa.gov/gmd/ccgg/trends_ch4

•  COVID-19 lockdown causes unprecedented drop in global CO2 emissions in 2020 - Gobal Carbon Project
https://www.globalcarbonproject.org/carbonbudget/20/files/International_FutureEarth_GCB2020.pdf

• Global Average Temperatures in 2020 Reached a RECORD HIGH of 1.55 C above PreIndustrial in 1750 - by Paul Beckwith 
https://www.youtube.com/watch?v=O0lgTAEUYyA

• Edge of Extinction: Maybe I’m Wrong - by Guy McPherson
https://guymcpherson.com/2021/01/edge-of-extinction-maybe-im-wrong

• Extinction
https://arctic-news.blogspot.com/p/extinction.html


Tuesday, December 17, 2019

Extinction in 2020?


Above image depicts how humans could go extinct as early as 2020. The image was created with NASA LOTI 1880-Nov.2019 data, 0.78°C adjusted to reflect ocean air temperatures (as opposed to sea surface temperatures), to reflect higher polar temperature anomalies (as opposed to leaving out 'missing' data) and to reflect a 1750 baseline (as opposed to a 1951-1980 baseline), with two trends added. Blue: a long-term trend based on Jan.1880-Nov.2019 data. Red: a short-term trend, based on Jan.2009-Nov.2019 data, to illustrate El Niño/La Niña variability and how El Niño could be the catalyst to trigger huge methane releases from the Arctic Ocean.

How was above image created? Let's first look at the baseline. The NASA default baseline is 1951-1980. The added trend in the image below shows early 1900s data to be well below this 1951-1980 baseline. In this analysis, a 0.28°C adjustment was therefore used to reflect this, and to reflect a 1750 baseline, a further 0.3°C was used, adding up to a 0.58°C baseline adjustment.


Furthermore, the NASA Land+Ocean temperature index (LOTI) uses sea surface temperatures, but ocean air temperatures seem more appropriate, which adds a further 0.1°C adjustment. Also, when comparing current temperatures with preindustrial ones, it's hard to find data for the polar areas. Treating these data as 'missing' would leave important heating out of the picture. After all, the polar areas are heating up much faster than the rest of the world, and especially so in the Arctic region. Therefore, a further 0.1°C adjustment was used to reflect higher polar temperature anomalies, resulting in the above-mentioned 0.78°C adjustment.

Finally, the red trend illustrates El Niño/La Niña variability. As discussed in a recent post, an El Niño is forecast for 2020 and this could be the catalyst to trigger huge methane releases from the Arctic Ocean.

The image below shows El Niño/La Niña variability going back to 1950, added to the NOAA monthly temperature anomaly.



As said, the Arctic region is heating up much faster than the rest of the world. There are several reasons why this is the case. Decline of the sea ice makes that less sunlight gets reflected back into space and that more sunlight is reaching the Arctic Ocean. This also causes more water vapor and clouds to appear over the Arctic Ocean. Furthermore, Arctic sea ice has lost most of the thicker multi-year ice that used to extend meters below the surface, consuming huge amounts of ocean heat entering the Arctic Ocean along ocean currents from the North Atlantic and the North Pacific oceans.

[ created with NOAA Arctic Report Card 2019 image ]
Above-mentioned feedbacks (albedo changes and more water vapor and clouds) contribute to higher temperatures in the Arctic. Furthermore, as the temperature difference between the North Pole and the Equator narrows, the jet stream changes, which can lead to further Arctic heating, i.e. higher temperatures of the atmosphere over the Arctic Ocean and over land around the Arctic Ocean, which in turn causes higher temperatures of the water flowing into the Arctic Ocean from rivers.

Furthermore, jet stream changes can also cause additional heating of parts of the Pacific Ocean and the Atlantic Ocean.

[ click on images to enlarge ]
Above image shows that sea surface temperature anomalies off the East Coast of North America as high as 13.6°C or 24.4°F were recorded on December 18, 2019.

Ocean currents can bring huge amounts of heat into the Arctic Ocean, and this can be amplified due to cyclones speeding up the inflow of water from the Atlantic Ocean and the Pacific Ocean into the Arctic Ocean.


As above image shows, the temperature rise of the oceans on the Northern Hemisphere is accelerating. This constitutes a critical tipping point, i.e. there are indications that a rise of 1°C will result in most of the sea ice underneath the surface to disappear. This sea ice used to consume the inflow of warm, salty water from the Atlantic Ocean and the Pacific Ocean. So, while there may still be sea ice left at the surface, since low air temperatures will cause freezing of surface water, the latent heat buffer has gone.


As long as there is sea ice, this will keep absorbing heat as it melts, so the temperature will not rise at the sea surface. The amount of energy absorbed by melting ice is as much as it takes to heat an equivalent mass of water from zero to 80°C.

The danger is that, as Arctic Ocean heating accelerates further, hot water will reach sediments at the Arctic Ocean seafloor and trigger massive methane eruptions, resulting in a huge abrupt global temperature rise. As discussed in an earlier post, a 3°C will likely suffice to cause extinction of humans.


Earlier this year, an Extinction Alert was issued, followed by a Stronger Extinction Alert.

In a rapid heating scenario:
  1. a strong El Niño would contribute to
  2. early demise of the Arctic sea ice, i.e. latent heat tipping point +
  3. associated loss of sea ice albedo,
  4. destabilization of seafloor methane hydrates, causing eruption of vast amounts of methane that further speed up Arctic warming and cause
  5. terrestrial permafrost to melt as well, resulting in even more emissions,
  6. while the Jet Stream gets even more deformed, resulting in more extreme weather events
  7. causing forest fires, at first in Siberia and Canada and
  8. eventually also in the peat fields and tropical rain forests of the Amazon, in Africa and South-east Asia, resulting in
  9. rapid melting on the Himalayas, temporarily causing huge flooding,
  10. followed by drought, famine, heat waves and mass starvation, and
  11. collapse of the Greenland Ice Sheet.
[ from an earlier post ]

The precautionary principle calls for appropriate action when dangerous situations threaten to develop. How can we assess such danger? Risk is a combination of probability that something will eventuate and severity of the consequences. Regarding the risk, there is growing certainty that climate change is an existential threat, as discussed in a recent post. There's a third dimension, i.e. timescale. Imminence alone could make that a danger needs to be acted upon immediately, comprehensively and effectively. While questions may remain regarding probability, severity and timescale of the dangers associated with climate change, the precautionary principle should prevail and this should prompt for action, i.e. comprehensive and effective action to reduce damage is imperative and must be taken as soon as possible.

The image below gives a visual illustration of the danger.


Polynomial trendlines can point at imminent danger by showing that acceleration could eventuate in the near future, e.g. due to feedbacks. Polynomial trendlines can highlight such acceleration and thus warn about dangers that could otherwise be overlooked. This can make polynomial trendlines very valuable in climate change analysis. In the image below, the green linear trend and the blue polynomial trend are long-term trends (based on Jan.1880-Nov.2019 data), smoothing El Niño/La Niña variability, but the blue polynomial trend better highlights the recent temperature rise than the green linear trend does. The red short-term trend (based on Jan.2009-Nov.2019 data) has the highest R² (0.994) and highlights how El Niño could be the catalyst for huge methane eruptions from the Arctic Ocean, triggering a huge global temperature rise soon.


The image below, from an earlier post, explains the speed at which warming elements can strike, i.e. the rise could for a large part occur within years and in some cases within days and even immediately.


As the image below shows, peak methane levels as high as 2737 parts per billion (ppb) were recorded by the MetOp-2 satellite in the afternoon of December 20th, 2019, at 469 mb. Ominously, a large part of the atmosphere over the East Siberian Arctic Shelf (ESAS) is colored solid magenta, indicating methane levels above 1950 ppb.



The situation is dire and calls for immediate, comprehensive and effective action, as described in the Climate Plan.



Links

• NASA - GISS Surface Temperature Analysis (GISTEMP v4)
https://data.giss.nasa.gov/gistemp/maps/index_v4.html

• NOAA Northern Hemisphere ocean temperature anomalies through November 2019
https://www.ncdc.noaa.gov/cag/global/time-series/nhem/ocean/1/11/1880-2019

• NOAA - Monthly temperature anomalies versus El Niño
https://www.ncdc.noaa.gov/sotc/global/201911/supplemental/page-3

• 2020 El Nino could start 18°C temperature rise
https://arctic-news.blogspot.com/2019/11/2020-el-nino-could-start-18-degree-temperature-rise.html

• NOAA Arctic Report Card 2019
https://www.arctic.noaa.gov/Report-Card/Report-Card-2019

• Critical Tipping Point Crossed In July 2019
https://arctic-news.blogspot.com/2019/09/critical-tipping-point-crossed-in-july-2019.html

• Most Important Message Ever
https://arctic-news.blogspot.com/2019/07/most-important-message-ever.html

• Accelerating greenhouse gas levels
https://arctic-news.blogspot.com/2019/11/accelerating-greenhouse-gas-levels.html

• Debate and Controversy
https://arctic-news.blogspot.com/p/debate.html

• Extinction Alert
https://arctic-news.blogspot.com/2019/02/extinction-alert.html

• Stronger Extinction Alert
https://arctic-news.blogspot.com/2019/03/stronger-extinction-alert.html

• Abrupt Warming - How Much And How Fast?
http://arctic-news.blogspot.com/2017/05/abrupt-warming-how-much-and-how-fast.html

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html



Wednesday, April 17, 2019

How long do we have?

The March 2019 temperature is in line with an earlier analysis that 2019 could be 1.85°C warmer than preindustrial and that a rapid temperature rise could take place soon, as illustrated by the image below.


A catastrophe of unimaginable proportions is unfolding. Life is disappearing from Earth and all life could be gone within a decade. At 5°C of warming, most life on Earth will have disappeared. When looking at near-term human extinction, 3°C will likely suffice. Study after study is showing the size of the threat, yet many people seem out to hide what we're facing.

Above image asks 'How long do we have?' The image is created with NASA LOTI data, adjusted 0.78°C to reflect a 1750 baseline, ocean air temperature and higher polar anomaly. Trends are added based on 1880-2019 (purple) and 2000-2019 data (red). The long-term purple trend points at 2025 as the year when 3°C rise from preindustrial could be crossed, while the red trend that focuses on short-term events shows how a 3°C rise from preindustrial could be reached as early as in 2020.

The chart below shows elements contributing to the warming, adding up to a rise of as much as 18°C by 2026.

[ from an earlier post ]
The situation is dire and calls for comprehensive and effective action, as described at the Climate Plan.


If we accept that crimes against humanity include climate crimes, then politicians who inadequately act on the unfolding climate catastrophe are committing crimes against humanity and they should be brought before the International Criminal Court in The Hague, the Netherlands.




Links

• Co-extinctions annihilate planetary life during extreme environmental change, by Giovanni Strona and Corey Bradshaw (2018)
https://www.nature.com/articles/s41598-018-35068-1

• How much warming have humans caused?
https://arctic-news.blogspot.com/2016/05/how-much-warming-have-humans-caused.html

• Extinction
https://arctic-news.blogspot.com/p/extinction.html

• A rise of 18°C or 32.4°F by 2026?
https://arctic-news.blogspot.com/2019/02/a-rise-of-18c-or-324f-by-2026.html

• Stronger Extinction Alert
https://arctic-news.blogspot.com/2019/03/stronger-extinction-alert.html

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html


Thursday, April 13, 2017

The Methane Threat

Carbon dioxide levels in the atmosphere are accelerating. As illustrated by the image below, a linear trend hardly catches the acceleration, while a polynomial trend does make a better fit. The polynomial trend points at CO₂ levels of 437 ppm by 2026.


EPA animation: more extreme heat
This worrying acceleration is taking place while energy-related have been virtually flat over the past few years, according to figures by the EIA and by the Global Carbon Project. So, what makes growth in CO₂ levels in the atmosphere accelerate? As earlier discussed in this and this post, growth in CO₂ levels in the atmosphere is accelerating due to continued deforestation and soil degradation, due to ever more extreme weather events and due to accelerating warming that is making oceans unable to further take up carbon dioxide.


Ocean warming is accelerating on the Northern Hemisphere, as illustrated by above image, and a warmer Atlantic Ocean will push ever warmer water into the Arctic Ocean, further speeding up the decline of the sea ice and of permafrost.

[ click on images to enlarge ]
Loss of Northern Hemisphere snow cover is alarming, especially in July, as depicted in above image. The panel on the left shows snow cover on the Northern Hemisphere in three areas, i.e. Greenland, North America and Eurasia. The center panel shows North America and the right panel shows Eurasia. While Greenland is losing huge amounts of ice from melting glaciers, a lot of snow cover still remains present on Greenland, unlike the permafrost in North America and especially Eurasia, which has all but disappeared in July.

[ for original image, see 2011 AGU poster ]
Worryingly, the linear trend in the right panel points at zero snow cover in 2017, which should act as a warning that climate change could strike a lot faster than many may expect.

A recently-published study warns that permafrost loss is likely to be 4 million km² (about 1.5 million mi²) for each 1°C (1.8°F) temperature rise, about 20% higher than previous studies. Temperatures may well rise even faster, due to numerous self-reinforcing feedback loops that speed up the changes and due to interaction between the individual warming elements behind the changes.

[ Arctic sea ice, gone by Sept. 2017? ]
One of the feedbacks is albedo loss that speeds up warming in the Arctic, in turn making permafrost release greenhouse gases such as carbon dioxide, nitrous oxide and methane.

Higher temperatures on land will make warmer water from rivers enter the Arctic Ocean and trigger wildfires resulting in huge emissions including black carbon that can settle on sea ice.

Given the speed at which many feedbacks and the interaction between warming elements can occur, Arctic sea ice volume may decline even more rapidly than the image on the right may suggest.
[ Record sea ice volume anomalies since end 2016 ]

Ominously, sea ice volume anomalies have been at record levels for time of year since end 2016 (Wipneus graph right, PIOMAS data).

As the Gulf Stream pushes warmer water into the Arctic Ocean, there will no longer be a large buffer of sea ice there to consume the heat, as was common for the entire human history.

Moreover, forecasts are that temperatures will keep rising throughout 2017 and beyond.
The Australian Bureau of Meteorology reports that seven of eight models indicate that sea surface temperatures will exceed El Niño thresholds during the second half of 2017.

The image on the right, by the ECMWF (European Centre for Medium-Range Weather Forecasts), indicates an El Niño that is gaining strength.

For more than half a year now, global sea ice extent has been way below what it used to be, meaning that a huge amount of sunlight that was previously reflected back into space, is now instead getting absorbed by Earth, as the graph below shows.
[ Graph by Wipneus ]
Where can all this extra heat go? Sea ice will start sealing off much of the surface of the Arctic Ocean by the end of September 2017, making it hard for more heat to escape from the Arctic Ocean by entering the atmosphere.

The Buffer has gone, feedback #14 on the Feedbacks page
It looks like much of the extra heat will instead reach sediments at the seafloor of the Arctic Ocean that contain huge amounts of methane in currently still frozen hydrates.

[ click on image to enlarge ]
The danger is that more and more heat will reach the seafloor and will destabilize methane hydrates contained in sediments at the bottom of the Arctic Ocean, resulting in huge methane eruptions.

As the image on the right shows, a polynomial trend based on NOAA July 1983 to January 2017 global monthly mean methane data, points at twice as much methane by 2034. Stronger methane releases from the seafloor could make such a doubling occur much earlier.

Meanwhile, methane levels as high as 2592 ppb were recorded on April 17, 2017, as shown by the image below. The image doesn't specify the source of the high reading, but the magenta-colored area over the East Siberian Sea (top right) looks very threatening.


We already are in the Sixth Mass Extinction Event, given the rate at which species are currently disappearing from Earth. When taking into account the many elements that are contributing to warming, a potential warming of 10°C (18°F) could take place, leading to a rapid mass extinction of many species, including humans.

[ Graph from: Which Trend is Best? ]
How long could it take for such warming to eventuate? As above image illustrates, it could happen as fast as within the next four years time.

The situation is dire and calls for comprehensive and effective action, as described at the Climate Plan.


Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• Extinction
https://arctic-news.blogspot.com/p/extinction.html

• How much warming have humans caused?
https://arctic-news.blogspot.com/2016/05/how-much-warming-have-humans-caused.html

• Accelerating growth in CO₂ levels in the atmosphere
https://arctic-news.blogspot.com/2017/02/accelerating-growth-in-co2-levels-in-the-atmosphere.html

• An observation-based constraint on permafrost loss as a function of global warming, by Chadburn et al. (2017)
http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3262.html

• Reduction of forest soil respiration in response to nitrogen deposition, by Janssens et al. (2010)
http://www.nature.com/ngeo/journal/v3/n5/full/ngeo844.html

• Methane Erupting From Arctic Ocean Seafloor
https://arctic-news.blogspot.com/2017/03/methane-erupting-from-arctic-ocean-seafloor.html

• Warning of mass extinction of species, including humans, within one decade
https://arctic-news.blogspot.com/2017/02/warning-of-mass-extinction-of-species-including-humans-within-one-decade.html