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Sunday, January 31, 2016

Arctic sea ice area at record low for time of year

Arctic sea ice area on January 28, 2016, was only 12.17902 million square km. At this time of year, sea ice area hasn't been as low as this for at least since satellite records started in 1979, as illustrated by the image below.

based on image from: arctic.atmos.uiuc.edu/cryosphere/arctic.sea.ice.interactive.html
Furthermore, on January 29, 2016, Arctic sea ice reached its second lowest extent since the satellite records began, as the image below shows.

based on image from: nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph

Why is sea ice at record low?

The sea ice is in a bad shape due to very high temperatures. A forecast for January 30, 2016, shows surface temperatures over the Arctic that are 2.7°C (4.86°F) warmer than they were in 1979-2000. The image below further illustrates this, showing temperature anomalies at the top end of the scale, i.e. 20°C (36°F) above 1979-2000, in many places in the Arctic.


At this time of year, there is very little sunshine in the Arctic. Therefore, these anomalies are caused by sea water that is warmer than it used to be. The image below shows that on January 24, 2016, sea surface temperature was 12.3°C (54.2°F) at a location near Svalbard marked by the green circle, a 10.4°C (18.7°F) anomaly.


Such anomalies are in turned caused by water that is much warmer than it used to be, and that is being carried by the Gulf Stream all the way into the Arctic Ocean.

Water much warmer off the North American coast

The water off the coast of North America is much warmer than it used to be due to emissions that extend from North America over the Atlantic Ocean due to the Coriolis effect. The image below, from an earlier post, shows carbon dioxide levels as high as 511 ppm over New York on November 5, 2015, and as high as 500 ppm over the water off the coast of coast of New Jersey on November 2, 2015.

from the post: 2015 warmest year on record
As discussed at an earlier post, also relevant are other emissions such as carbon monoxide that depletes hydroxyl, making it harder for methane to be oxidized. Below is an update on carbon monoxide levels.


These emissions heat up the Gulf Stream and make that ever warmer water is carried underneath the sea surface all the way into the Arctic Ocean, while little heat transfer occurs from ocean to atmosphere, due to the cold freshwater lid on the North Atlantic.

Arctic sea ice in uncharted territory

Update 1: For the time of the year, Arctic sea ice is now at a record low since satellite records started in 1979, both for area and extent. The image below shows Arctic sea ice area up to February 1, 2016, when area was 12.27298 million square km.

based on image from: arctic.atmos.uiuc.edu/cryosphere/arctic.sea.ice.interactive.html
The image below shows Arctic sea ice extent up to February 2, 2016, when extent was 13.932 million square km.

based on image from: nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph
Update 2: For the time of the year, Arctic sea ice remains at a record low since satellite records started in 1979, both for area and extent. The image below shows Arctic sea ice area up to February 4, 2016, when area was 12.30656 million square km.

[ click on image to enlarge ]
Comprehensive and effective action is needed

This situation spells bad news for what will happen later in 2016, also given the current El Niño. Less sea ice means that less sunlight is reflected back into space, resulting in more heat being absorbed by the Arctic Ocean.

As more heat reaches the bottom of the Arctic Ocean, the risk increases that heat will penetrate and destabilize sediments containing methane hydrates. Methane escaping from hydrates could strongly accelerate warming in the Arctic, causing further melting of the sea ice, in a spiral of warming that could escalate into runaway warming.

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


Related posts

- Why America should lead on climate
arctic-news.blogspot.com/2016/01/why-america-should-lead-on-climate.html

- Sea surface warmest on record
arctic-news.blogspot.com/2015/10/september-2015-sea-surface-warmest-on-record.html

- Climate Plan
arctic-news.blogspot.com/p/plan.html

- 2015 warmest year on record
arctic-news.blogspot.com/2015/12/2015-warmest-year-on-record.html

Arctic sea ice area on January 28, 2016, was only 12.17902 million square km. At this time of year, sea ice area hasn't...
Posted by Sam Carana on Sunday, January 31, 2016

Saturday, January 23, 2016

Why America should lead on climate

There are many reasons why America should take the lead in action on climate change. 

It's fair and in everyone's interest that America takes the lead

It's fair that those who pollute most, do most to clean things up. America's current and historic emissions are huge, while a lot of what has been produced elsewhere is also consumed in America. Moreover, it's in everyone's interest if America takes the lead. That is confirmed by studies such as this one, showing that there are no technical or economic barriers against cleaning things up. Doing so has many benefits, including job and investment opportunities, and scope for exports. In order for American industries, such as car manufacture, to remain competitive with products from overseas, they must clean up their act. In addition, there are many health and the environmental benefits, while shifting to clean energy will remove perceived needs for America to send military forces across the world to protect global supply lines of fossil fuel.

Legal obligations to act

There are also legal obligations for America to act. Back in 2007, the Supreme Court ruled in Mass. v. EPA that the EPA must act on any air pollutant that endangers public health or welfare. The EPA subsequently found this to be the case for six greenhouse gases and took action, including by issuing plans to limit carbon emissions from power plants. More recently, the United States Court of Appeals for the DC Circuit ruled in favor of the EPA plans.

Furthermore, as Michael Burger points out, Section 115 of the Clean Air Act also authorizes the EPA to act on emissions that contribute to air pollution that endangers public health or welfare in other countries, the more so where the other countries provide the U.S. with reciprocal protections. At the Paris Agreement, such reciprocity was affirmed by some 190 nations (accounting for over 93% of current GHG emissions) pledging to hold the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels.

In other words, no new laws are needed and action can and should be taken now, as this blog has pointed out for years, e.g. in this 2014 post that featured the image below.




The threat of methane eruptions from the Arctic Ocean seafloor calls for urgent action

This blog has repeatedly pointed at another reason why especially America must act, and must do so rapidly, comprehensively and effectively. In October 2015, oceans reached record high temperatures, especially on the Northern Hemisphere, as illustrated by the image below.

Northern Hemisphere October ocean temperatures based on NOAA 1880-2015 data - plot area goes from 1900 to 2050 and from -1 to 4 degrees Celsius above baseline, i.e. compared to the period 1901-2000, the 20th century average.
Above image features a trendline showing that oceans on the Northern Hemisphere could, by the year 2043, be 4°C or 7.2°F warmer than the 20th century average. Increasingly, methane levels over the Arctic Ocean are showing strong increases from October onward, as huge amounts of ocean heat are reaching the seafloor of the Arctic Ocean from that month onward.

North America contributes strongly to accelerating warming of the Arctic Ocean. The Coriolis Effect makes that high levels of emissions originating from North America are extending over the Atlantic Ocean, and are warming up waters off the east coast of North America, as illustrated by the image below.

Top left: CO2 414 ppb green circle, up to 433 ppm in New Jersey. Top right: CO 274 ppb green circle, up to 890 ppb in New Jersey. Bottom left: Jet Stream 250 hPa. Bottom right: Sea surface temperature anomaly 8.5°C/15.3°F green circle.
2015 maximum nightly sea surface temperature anomaly
Carbon dioxide emissions are important, but also relevant are other emissions such as carbon monoxide that depletes hydroxyl, making it harder for methane to be oxidized.

As emissions keep rising, the Gulf Stream will carry ever warmer water into the Arctic Ocean, resulting in greater melting of the sea ice and associated albedo changes that in turn accelerate warming in the Arctic.

Surface temperature anomaly Jan 21, 2015 - Jan 20, 2016
 
This is further illustrated by the images on the right. The top image shows 2015 maximum nightly sea surface temperature anomalies, with anomalies of 5°C off the North American east coast as well as in the Arctic Ocean.

The second image on the right illustrate the extent at which warming in the Arctic Ocean is accelerating, compared to the rest of the world. The image also shows the cold freshwater lid over the North Atlantic.

Temperature anomaly forecast for January 28, 2016
 
As the temperature difference between the Arctic and the equator decreases, the jet stream gets more elongated, at times moving all across the Arctic Ocean. This is one of a multitude of feedbacks that contribute to accelerating warming of the Arctic Ocean. The result is illustrated by the third image on the right, showing strong warming over most of the Arctic Ocean, while at the same time some places on land at higher latitudes north are experiencing extremely cold conditions.

descending cold freshwater on January 25, 2016
Another one of such feedbacks is that warmer water off the coast of North America will result in stronger winds moving over the North Atlantic toward the Arctic Ocean. This can also speed up ocean currents, so it can result in more heat being carried toward the Arctic Ocean both in the atmosphere and the water.

Meltwater from glaciers and sea ice can descend along the edges of Greenland into the North Atlantic, forming a cold freshwater lid on the North Atlantic, where it accumulates at the surface over the years, as illustrated by the image on the right that points at a -4°C or -7.1°F anomaly compared to 1981-2011.

cold freshwater lid over the North Atlantic
In addition, precipitation (rain, snow, hail, fog, etc.) can further contribute to expansion of this cold freshwater lid over the North Atlantic, as illustrated by the images on the right.

While this cold freshwater may constitute a barrier that slows the flow of warm water toward the Arctic Ocean at the surface, the danger is that it prevents heat transfer to the atmosphere from warm water flowing below the sea surface, with the net result of more heat arriving in the Arctic Ocean.

Furthermore, if this cold freshwater lid also prevents water from sinking deeper in the North Atlantic, this may also contribute to more warm water arriving in the Arctic ocean, as illustrated by the bottom image on the right.

Such feedbacks can dramatically accelerate warming of Arctic Ocean, resulting in heat destabilizing sediments that can contain huge amounts of methane.

In conclusion, America must take the lead in action on climate change. It's fair to do so, it will benefit everyone, there are legal obligations to do so and there is great urgency to act in the light of looming methane eruptions from the seafloor of the Arctic Ocean.

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



In October 2015, oceans reached record high temperatures, especially on the Northern Hemisphere. The image features a...
Posted by Sam Carana on Saturday, January 23, 2016

Thursday, January 14, 2016

Greenhouse gas levels and temperatures keep rising

At the Paris Agreement, nations pledged to cut emissions and avoid dangerous temperature rises. Yet, the rise in greenhouse gas levels and temperatures appears to be accelerating.

Record growth of carbon dioxide levels at Mauna Loa

Annual mean carbon dioxide level measured at Mauna Loa, Hawaii, grew by 3.17 ppm (parts per million) in 2015, a higher growth rate than in any year since the record started in 1959.


As above image shows, a polynomial trendline added to the data points at a carbon dioxide growth rate of 4 ppm by the year 2024 and 5 ppm by the year 2028. 

At the start of the Industrial Revolution, the carbon dioxide level in the atmosphere was about 280 ppm. On January 11, 2016, as above image shows, carbon dioxide level at Mauna Loa, Hawaii, was 402.1 ppm. That's some 143% times what the upper level of carbon dioxide was in pre-industrial times over at least the past 400,000 years, as the image further below illustrates.

At higher northern latitudes, carbon dioxide levels are higher than elsewhere on Earth, as illustrated by above image. These high greenhouse gases contribute to accelerated warming of the Arctic. 

Methane levels rising even faster than CO2 levels, especially over Arctic Ocean

Historically, methane levels have been moving up and down between a window of 300 and 700 ppb. In modern times, methane levels have been rising even more rapidly than carbon dioxide levels, as illustrated by the image below, from an earlier post.

As above image illustrates, the mean level of 1839 ppb that was reached on September 7, 2014, is some 263% of the ~700 ppb that historically was methane's upper level.

The image below, from an earlier post, shows the available World Meteorological Organisation (WMO) annual means, i.e. from 1984 through to 2014, with added polynomial trendline based on these data. The square marks a high mean 2015 level, from NOAA's MetOp-2 satellite images, and it is added for comparison, so it does not influence the trendline, yet it does illustrate the direction of rise of methane levels and the threat that global mean methane levels will double well before the year 2040.


Recently, some very high peak levels have been recorded, including a reading of 2745 ppb on January 2, 2016, and a reading of 2963 ppb on January 8, 2016, shown below.



These high readings illustrate the danger that, as warmer water reaches the seafloor of the Arctic Ocean, it will increasingly destabilize sediments that can contain huge amounts of methane in the form of free gas and hydrates. Images associated with these high readings show the presence of high methane levels over the Arctic Ocean, indicating that these high peaks originate from the Arctic ocean and that sediments at the seafloor of the Arctic Ocean are destabilizing. The danger is that these peaks will be followed up by even stronger abrupt releases from the seafloor of the Arctic Ocean, as water temperatures keep rising.

Rising temperatures

Global mean temperature in 2015 was 0.87°C (~1.6°F) higher than in 1951-1980. 

Above image shows NASA data with a polynomial trendline added that points at a 2015 temperature that is more than 1.1°C (~2.03°F) higher than it was in 1900.

The image on the right shows that it was 1.17°C warmer in 2015 than it was in the period 1890-1910.

Additionally, some 0.3°C warming had already taken place by the year 1900, as discussed in an earlier post.

Together, that makes that 2015 temperatures were 1.47°C above pre-industrial levels.

Furthermore, temperatures did rise steeply over the course of the year 2015.

By the end of the year 2015, the temperature rise was even stronger than the average for 2015 would indicate, as illustrated by the image on the right.

It is now 2016 and temperatures are still rising. In other words, it now is more than 1.5°C or 2.7°F warmer than in pre-industrial times. In conclusion, we have already crossed the 1.5°C guardrail that the Paris Agreement had pledged to try and limit global warming to. 

What is the prognosis for the temperature rise from here onward? The current El Niño is expected to continue well into 2016. Even if the El Niño slows down, it will by then likely have contributed to huge losses of snow and ice cover, including sea ice melt in the Arctic. The resulting albedo changes alone may well have an even stronger warming effect than the El Niño, while there are further feedbacks such as disruption of the jet stream and methane eruptions from the seafloor of the Arctic Ocean.

The image below shows that, when that same trendline featuring in above graph is extended into the future, it points at a 2°C or 3.6°F global temperature anomaly rise before the year 2030, a rise of about 4°C or 7.2°F by 2040, and a 10°C or 18°F rise before the year 2060. That would be a rise compared to the period 1951-1980, i.e. warming compared to pre-industrial levels would be even more severe.


Three points are important to help more fully grasp the predicament we are in:
  1. At higher latitudes of the Northern Hemisphere, temperatures are rising faster than globally, as illustrated by above image that shows that a 10°C rise could hit the Arctic by 2030. 
  2. Summer peaks will be even more devastating than annual averages. 
  3. The rise of temperatures on land will be steeper than the rise in the combined land-ocean temperatures, as illustrated by the image below that shows that a 3°C rise on land could occur well before the year 2030.  


Comprehensive and effective action needed

As greenhouse gases and temperatures keep rising, the heat will be felt earliest and most severely on land, during the northern summer and in the Arctic.

One big danger is that soil that was previously frozen will become exposed and will start releasing huge amounts of carbon, in the form of carbon dioxide or methane.

Furthermore, boreal forest, tundra and peats bogs are at risk of firestorms that will also come with huge amounts of emissions.

All this will make the rise in temperature speed up even more, with much of the soot from firestorms in Siberia settling on the Himalaya Tibetan plateau, melting the glaciers there and causing short-term flooding followed by rapid decrease of the flow of ten of Asia’s largest river systems that originate there, with more than a billion people’s livelihoods depending on the continued flow of this water.

Again, the reason why temperatures look set to rise so abruptly and dramatically in the Arctic is feedbacks, as discussed as the feedbacks page. The biggest danger that comes with these rapidly rising temperatures in the Arctic is that large methane eruptions from the seafloor of the Arctic Ocean will further heat up the atmosphere, at first in hotspots over the Arctic, and eventually around the globe, while also causing huge temperature swings and extreme weather events, further contributing to increasing depletion of fresh water and food supply.

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

Below is an image by Malcolm Light, which updates an image that appeared in an earlier post




Annual mean carbon dioxide level measured at Mauna Loa, Hawaii, grew by 3.17 ppm (parts per million) in 2015, a higher...
Posted by Sam Carana on Thursday, January 14, 2016

Tuesday, January 5, 2016

Arctic Sea Ice At Record Low

Arctic sea ice extent on January 4, 2016, was at a record low for the time of the year, as illustrated by the image below.


Arctic sea ice will typically reach its maximum extent in March. In 2015, sea ice extent was very low in March (see blue line in above image), and the outlook for this year is even more grim, as oceans get warmer and El Niño is still gaining in strength.

Below is a comparison of sea ice thickness (in m) on January 4th for the years 2012, 2015 and 2016.


Below is an update showing Arctic sea ice extent as on January 6, 2016, at the bottom left corner, marked with the red dot.



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



Arctic sea ice extent on January 4, 2016, was at a record low for the time of the year. Arctic Sea Ice At Record Lowhttp://arctic-news.blogspot.com/2016/01/arctic-sea-ice-at-record-low.html
Posted by Sam Carana on Tuesday, January 5, 2016