Thursday, May 11, 2017

Arctic Sea Ice May 2017

Last year, the Arctic was some 3.5°C warmer than it was at the start of the Industrial Revolution. Was this 3.5°C a spike or was it part of a trend pointing at even higher temperature anomalies this year and the following years?


Above image shows NASA annual mean 64°N-90°N land-ocean temperature anomalies from 1951-1980, with +0.59°C added for the rise from 1750 to 1951-1980. A polynomial trend is added (based on 1880-2016 data), pointing at 4.5°C anomaly by 2019.

Will the Arctic keep warming over the coming years in line with this trend? Let's have a look at what affects temperatures in the Arctic most, specifically Ocean Heat, Sea Ice, Land Temperatures and Emissions.

1. Ocean Heat

Warmer Oceans on the Northern Hemisphere will contribute strongly to warming in the Arctic. Here's a graph showing a trend pointing at continued warming of the oceans on the Northern Hemisphere.

Will oceans keep warming like that, in particular the North Atlantic? The Coriolis force keeps pushing warm water of the North Atlantic along the Gulf Stream toward the Arctic Ocean.

On the image on the right, the Gulf Stream shows up as the warmer water (orange and yellow) off the coast of North America.

Thus, as oceans keep warming, warmer water will reach the Arctic Ocean, melting the sea ice from below.

The image on the right shows that the sea surface was 9.3°C or 16.8°F warmer than 1981-2011 on May 7, 2017, at the location marked by the green circle.

2. Sea ice

Meanwhile, the sun will warm up the sea ice from above. The sea ice acts as a barrier, insulating the water of the Arctic Ocean from the heat from above. As long as there is sea ice, water just underneath the sea ice will stay close to freezing point.

Sea ice can strongly affect the amount of heat that is retained by Earth. Sea ice reflects most sunlight back into space, but in the absence of sea ice, most sunlight will instead be absorbed by oceans.

For almost a year now, global sea ice extent has been way below what it used to be, meaning that huge amounts of sunlight that were previously reflected back into space, are now instead getting absorbed by Earth, as shown by the graph below (by Wipneus).

Over the past 365 days, most of the Arctic has been more than 2.5°C or 4.5°F warmer than it was in 1981-2010, as the image on the right illustrates. Note also the anomalies around Antarctica. Decline of the snow and ice cover contributes strongly to these temperature anomalies.

When looking at albedo changes, sea ice area is an even more critical measure than sea ice extent. For a discussion of the difference between area and extent, see this NSIDC page. The image below shows trends for both Arctic and Antarctic sea ice area pointing downward.


When looking at sea ice volume, zero sea ice in September 2017 is within the margins of the trendline below on the right.

[ Arctic sea ice, gone by Sept. 2017? ]
Given the speed at which many feedbacks can kick in and the interaction between warming elements, Arctic sea ice volume could be zero by September 2017.

Arctic sea ice is at a record low volume for the time of the year (see graph below by Wipneus). This means that there is very little sea ice left to act as a buffer this year. Therefore, heat that won't be consumed in the process of melting the ice will instead speed up Arctic warming.

As said - less sea ice additionally makes that less sunlight will be reflected back into space, and that instead more heat will speed up Arctic warming.
As the sea ice gets thinner, it becomes more fragile. Furthermore, changes to the Jet Stream can fuel strong winds and waves, which are also more likely to hit the ice as the size of the open water increases.

The satellite image below of the Beaufort Sea shows that the sea ice is cracked in many places and broken into pieces by winds, waves, currents and ocean heat. A huge crack can be seen running along the Canadian Archipelago toward Greenland (bottom right on the image).


An animation (1.3 MB) is added at the end of this post showing the sea ice breaking into pieces in the Beaufort Sea from April 26 to May 10, 2017. It illustrates that a combined force of winds, waves, currents and ocean heat can break even the thicker ice into pieces, with the danger that all ice can be pushed out of the Arctic Ocean.

3. Temperatures on land

High temperatures on land will affect the Arctic in a number of ways. What kind of temperatures can be expected over the coming months, which are so critical for Arctic sea ice?

- Heatwaves

Heatwaves over the continents can more easily extend over the Arctic Ocean as the Northern Polar Jet Stream becomes more wavy. Heatwave conditions are more likely to occur as the jet stream is changing due to accelerated warming of the Arctic.

- Wildfires

High temperatures on land can also cause wildfires that can in turn cause huge quantities of emissions, including soot that when settling on snow and ice, can strongly speed up melting. The image below shows carbon dioxide as high as 607 ppm and carbon monoxide as high as 24.84 over Laos on May 4, 2017.


- Warm water from rivers flowing into the Arctic Ocean

Furthermore, high temperatures on land will warm up the water of rivers flowing into the Arctic Ocean.

- El Niño

An El Niño event can dramatically boost temperatures of the atmosphere. What are the projections for an El Niño in 2017? The image on the right, by the ECMWF (European Centre for Medium-Range Weather Forecasts), indicates an El Niño that is gaining strength.

4. Emissions and Greenhouse Gas Levels

Continued emissions and high greenhouse gas levels are responsible for warming of the planet. Have efforts to cut emissions been successful? Is growth in greenhouse gas levels slowing down? The image below shows accelerating growth of carbon dioxide levels recorded at Mauna Loa, Hawaii.

The image below shows carbon dioxide levels recorded at Barrow, Alaska.

The image below shows methane levels at Barrow, Alaska.
In conclusion, indications are that warming in the Arctic will continue in 2017, which spells bad news for Arctic sea ice and for the world at large, as discussed in earlier posts.

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

Monday, April 24, 2017

10°C or 18°F warmer by 2021?

Skyrocketing emissions

On April 21, 2017, at 15:00 UTC, it was as hot as 46.6°C/115.8°F in Guinea, in West-Africa (at the location marked by the green spot on the map below).


That same time and day, a little bit to the south, at a spot in Sierra Leona, a level of carbon monoxide (CO) of 15.28 parts per million (ppm) was recorded, while the temperature there was 40.6°C or 105.1°F. Earlier that day (at 13:30 UTC), levels of carbon dioxide (CO₂) of 569 ppm and of sulfur dioxide (SO₂) of 149.97 µg/m³ were recorded at that same spot, shown on the bottom left corner of the image below (red marker).


These high emissions carry the signature of wildfires, illustrating the threat of what can occur as temperatures keep rising. Further emissions that come with wildfires are black carbon and methane.


Above image shows methane levels on April 22, 2017, AM, at an altitude corresponding to 218 mb. Methane at this altitude is as high as 2402 ppb (magenta indicates levels of 1950 ppb and higher) and while the image doesn't specify the location of this peak, it looks related to the magenta-colored area over West Africa and this looks related to the wildfires discussed above. This wasn't even the highest level recorded that day. While at lower altitudes even higher methane levels were recorded that morning (as high as 2505 ppb), above image illustrates the contribution wildfires can make to methane growth at higher altitudes.


The table below shows the altitude equivalents in feet (ft), meter (m) and millibar (mb).
57,016 ft44,690 ft36,850 ft30,570 ft25,544 ft19,820 ft14,385 ft 8,368 ft1,916 ft
17,378 m13,621 m11,232 m 9,318 m 7,786 m 6,041 m 4,384 m 2,551 m 584 m
 74 mb 147 mb 218 mb 293 mb 367 mb 469 mb 586 mb 742 mb 945 mb


Above image compares mean methane levels on the morning of April 22 between the years 2013 to 2017, confirming that methane levels are rising most strongly at higher altitudes, say between 6 to 17 km (which is where the Troposphere ends at the Equator), as compared to altitudes closer to sea level. This was discussed in earlier posts such as this one.

On April 26, 2017, CO₂ levels at Mauna Loa, Hawaii spiked at 412.63 ppm.



As the image below shows, some hourly CO₂ averages for that day were well above 413 ppm.


These high CO₂ levels were likely caused by wildfires, particularly in Siberia.

CO₂ readings on April 26, 2017, 22:30 UTC
As said, besides emissions of CO₂, wildfires cause a lot of additional emissions, as illustrated by the images below.

As above image shows, methane levels as high as 2683 ppb were recorded on April 27, 2017. While the image doesn't specify where these high levels occurred, there are a lot of magenta-colored areas over Siberia, indicating levels over 1950 ppb. The image below shows carbon monoxide levels as high as 5.12 ppm near Lake Baikal on April 27, 2017.


As the image below shows, temperatures on April 28, 2017, were as high as 26.5°C or 79.6°F near Lake Baikal.


The satellite images below shows some of the wildfires. The images also show ice (in the left panel) over Lake Baikal on April 25, 2017, as well as over much of the Angara River that drains Lake Baikal. On April 28, 2017, much of that ice had melted (right panel).

[ click on images to enlarge ]
Warming oceans

Oceans are hit by high temperatures as well. The image below shows sea surface temperature anomalies (from 1981-2011) on April 21, 2017, at selected locations.



Accelerating temperature rises

The image below illustrates the danger of accelerating temperature rises.


Above image uses trendlines based on data dating back to 1880, which becomes less appropriate as feedbacks start to kick in that accelerate such temperature rises. Indeed, temperatures could rise even faster, due to feedbacks including the following ones:

Less sunlight getting reflected back into space

As illustrated by the image below, more ocean heat results in less sea ice. This makes that less sunlight gets reflected back into space and instead gets absorbed by the oceans.

[ Graph by Wipneus ]

More ocean heat escaping from the Arctic Ocean into the atmosphere

As discussed before, as less heat is mixed down to deeper layers of oceans, more heat accumulates at or just below the surface. Stronger storms, in combination with the presence of a cold freshwater lid on top of the North Atlantic, increase the possibility that more of this ocean heat gets pushed into the Arctic Ocean, resulting in sea ice loss, which in turn makes that more heat can escape from the Arctic Ocean to the atmosphere, while more clouds over the Arctic Ocean make that less heat can get radiated out into space. As the temperature difference between the Arctic Ocean and the Equator decreases, changes are occurring to the Northern Polar Jet Stream that further speed up warming of the Arctic.

More heat remaining in atmosphere due to less ocean mixing

As also discussed before, warmer water tends to form a layer at the surface that does not mix well with the water below. This stratification reduces the capability of oceans to take up heat and CO₂ from the atmosphere. Less take-up by oceans of CO₂ will result in higher CO₂ levels in the atmosphere, further speeding up global warming. Additionally, 93.4% of global warming currently goes into oceans. The more heat will remain in the atmosphere, the faster the temperature of the atmosphere will rise. As temperatures rise, more wildfires will erupt, adding further emissions, while heat-induced melting of permafrost will also cause more greenhouse gases to enter the atmosphere.

More seafloor methane entering the atmosphere

The prospect of more heat getting pushed from the Atlantic Ocean into the Arctic Ocean also comes with the danger of destabilization of methane hydrates at the seafloor of the Arctic Ocean. Importantly, large parts of the Arctic Ocean are very shallow, making it easy for arrival of more ocean heat to warm up these seas and for heat to destabilize sediments at the seafloor that can contain huge amounts of methane, resulting in eruptions of methane from the seafloor, with much the methane entering the atmosphere without getting decomposed by microbes in the water, since many seas are only shallow, as discussed in earlier posts such as this one.

These feedbacks are depicted in the yellow boxes on above diagram on the right.

How fast could temperatures rise?

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 rapid mass extinction of many species, including humans.
[ Graph from: Which Trend is Best? ]
So, how fast could such warming take place? 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

• Arctic Sea Ice Getting Terribly Thin


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


Wednesday, April 5, 2017

Gulf Stream is heating up

El Niño 2017 is strengthening. On March 24, temperatures in Africa were as high as 50.6°C or 123°F.


The image below shows wildfires hitting Northern China and Far East Russia on April 4, 2017. The Amur River, which forms the boundary between China and Russia, is visible on this Terra/MODIS satellite image, with red dots indicating wildfires.


Emissions associated with such wildfires can be huge, as illustrated by the image below. On April 4, 2017, sulfur dioxide (SO₂) levels were as high as 766.29 µg/m³ at a spot (marked by the green circle, left panel) north of the Amur River, in Russia, while carbon dioxide (CO₂) levels were as high as 513 parts per million at that same spot and carbon monoxide (CO) levels there were as high as 17,402 parts per billion.


These high sulfur dioxide levels indicate that sulfur that has over the past few decades been deposited there from smokestacks of coal-fired power plants, tailpipes of vehicles, etc., can re-enter the atmosphere as a result of wildfires, confirming the conclusion of earlier studies such as by Hegg et al.

This indicates that sulfur levels in the atmosphere are higher than previously estimated, given that most previous estimates were mainly based on real-time emissions from industrial activity at the time. When adding revolitalization of previously-deposited sulfur (due to wildfires) into the picture, estimates for such aerosols' masking effect of the full wrath of global warming will be higher than previously thought, and increasingly so, as wildfires are becoming painfully more common as Earth continues to warm up.

This also implies that it becomes increasingly plausible that, when aerosol levels suddenly drop during heatwaves, wet bulb temperature starts crossing sustainability limits for humans without air-conditioning. Note that in July 2016, weather conditions at a spot in the U.S. came perilously close to this limit.

What could further contribute strongly to a rapid rise in global temperature is the combination of decline of Earth's snow and ice cover and eruptions of methane from the seafloor of the Arctic Ocean.

The Gulf Stream is heating up as the 2017 El Niño strengthens, fueled by record low global sea ice extent, which means that a lot of extra heat is getting absorbed globally (image below, by Wipneus).


Both Arctic and Antarctic sea ice extent were are record low on April 1, 2017, as the images below show.

Sea surface temperatures were as much as 5.9°C or 10.6°F warmer than 1981-2011 at the location marked by the green circle on the image below.


Over the next half year, increasingly warm waters will be carried by the Gulf Stream from the coast of North America to the Arctic Ocean. As this warmer water arrives in the Arctic Ocean, there will no longer be a large buffer of sea ice there to consume the heat, as was common for the past thousands of years and longer. Additionally, warmer water looks set to arrive in an Arctic Ocean that will be heated up like we've never seen before, as so much of the sunlight reaching the surface of the Arctic Ocean doesn't get reflected back into space anymore and as temperatures again look set to reach record highs in the Arctic during the northern summer.

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 the Arctic Ocean by entering the atmosphere. The extremely dangerous situation is that 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.


An image in an earlier post showed many cracks in the sea ice north of Greenland. Above image shows that huge cracks are also present in the sea ice in the Beaufort Sea.


On the combination images above and below, high concentrations of methane show up all over the Arctic Ocean, specifically over the Beaufort Sea and over and around Greenland. Note also the methane showing up over Antarctica, as discussed in an earlier post.


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

•Earth losing her sea ice
https://arctic-news.blogspot.com/2017/03/earth-losing-her-sea-ice.html

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

• Nitrogen and sulfur emissions from the burning of forest products near large urban areas, Hegg et al. (1987)
http://onlinelibrary.wiley.com/doi/10.1029/JD092iD12p14701/full

• 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

• Low sea ice extent contributes to high methane levels at both poles