Tuesday, August 13, 2013

Arctic Ocean is turning red

The Arctic Ocean is turning red, as sea surface temperatures (SST) rise. The NOAA maps below, dated August 12, 2013, show sea surface temperature anomalies across the Arctic Ocean of up to 5°C (9°F). Virtually all areas were the sea ice has disappeared are now colored scarlet red.

[ click on image to enlarge ]
The (updated) animation below shows SST anomalies from June 3 to August 26, 2013.


For a full-size animation, see http://www.ospo.noaa.gov/Products/ocean/sst/anomaly/anim_full.html

Locally, the situation can be even worse. The NOAA map below, dated August 13, 2013, shows that areas where the sea ice has disappeared in the Arctic Ocean can be exposed to sea surface temperature anomalies higher than 8°C (14.4°F).


[ click on image to enlarge ]
These anomalies are very high, even when compared to some of the recent years, when the decline of sea ice extent didn't look as bad as it appears now.

Many people may only look at the sea ice, assuming that things are fine as long as there is no dramatic decrease in sea ice area or extent (see Cryosphere Today image right).

However, there are many other things to consider, as described in the earlier post Cyclone raging over thin ice. Most importantly, sea surface temperature anomalies this high are very alarming!

For comparison, the image below shows August sea surface temperature anomalies in 2007, 2010 and 1011.

from: http://www.arctic.noaa.gov/reportcard/ocean.html
These high sea surface temperature anomalies are firstly caused by higher sea and air temperatures as a result of global warming. Additionally, there are many feedbacks that accelerate the temperature rise in the Arctic, as discussed at the post Diagram of Doom. Local conditions can further accelerate the temperature rise in specific areas, such as where warm water from rivers flows into the Arctic Ocean.

As the map below shows, a number of large rivers end in the Kara Sea, where high temperatures have been recorded for some time.

map from: http://en.wikipedia.org/wiki/File:Rs-map.png
Another large river is the Mackenzie River, which ends in the Beaufort Sea, where sea surface temperatures of about 20°C (68°F) are currently recorded, as the image below illustrates.


Similarly, the NOAA image below shows that sea surface temperatures of up to 18°C (64.4°F) were recorded in the Bering Strait on August 12, 2013.


Note that the melting season still has quite a while to go. Arctic sea ice volume minimum is typically reached around halfway into September, which is more than one month away. On September 12-13, 2011, temperatures of 6-7°C were reached over East Siberian Arctic Shelf, and up to 9°C along the coast of Alaska.

The danger of this situation is that this dramatic rise in temperature anomalies will not remain restricted to surface waters, but that heat will penetrate the seabed which can contain huge amounts of methane in the form of hydrates and free gas in sediments.

Submarine pingoes: Indicators of shallow gas
hydrates in a pockmark at Nyegga, Norwegian Sea -
Hovland et al., Marine Geology 228 (2006) 15–23
At the moment, a cyclone is raging over the Arctic Ocean, and this causes warm surface waters to be mixed down, in many places all the way down to the seabed, due to the shallow nature of many of the seas in the Arctic Ocean.

As shown on the image right and also described at the FAQ page, there can be all kinds of fractures in the sediment, while there can also be conduits where methane has escaped earlier from hydrates, allowing heat to penetrate deep into the sediment and causing methane to escape.

Methane is kept stable inside hydrates as long as the temperature remains low. Since methane expand some 160 times in volume, compared to its compressed frozen state inside the hydrate, warming of even a small part of a hydrate can cause destabilization across the entire hydrate. It may take only a small rise in temperature of a single conduit in the sediment to set off a large abrupt release of methane, which subsequently threatens to cause further releases elsewhere in the Arctic Ocean and trigger runaway global warming, as described at the methane hydrates blog.

Arctic Death Spiral - Evolution to July 2013

Image by Andy Lee Robinson, from http://haveland.com/share/arctic-death-spiral.png
The video below is a visualization of the Arctic Death Spiral showing the evolution of the volume of sea-ice over time from 1979 to July 2013.

The rate of ice loss in the Arctic is staggering. Since 1979, the volume of Summer Arctic sea ice has declined by more than 80% and is accelerating faster than scientists believed it would, or even could melt.


Pitch of the notes are proportional to the average sea-ice volume for each month. Spectral filters are derived from the average sea-ice volume for each year. Produced using Perl and PovRay, Midi perl and Reason and Virtualdub on a cluster of Linux servers.


Above image is another way to visualize the data. It is a screenshot from the video below, by Andy Lee Robinson, illustrating the dramatic decline since 1979 until July 2013.

Andy Lee Robinson
The soundtrack "Arctic Requiem" also by Andy Lee Robinson, is available for free download: http://haveland.com/share/Arctic-Requiem.mp3

Sea Ice Volume is calculated using the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS, Zhang and Rothrock, 2003) developed at APL/PSC.

Source data is available from:
http://psc.apl.washington.edu/wordpress/research/projects/arctic-sea-ice-volume-anomaly/


Monday, August 12, 2013

More on Wildfires


Previous posts have highlighted the huge amounts of carbon dioxide, methane and soot being emitted as a result of wildfires. Apart from this, there are further important pollutants to consider in regard to their potential to contribute to warming, especially at high latitudes.

The image below, dated August 7, 2013, and kindly supplied by Leonid Yurganov, shows high levels of carbon monoxide as a result of wildfires in Siberia, reaching high up into the Arctic all the way to Greenland. 

[ click on image to enlarge ]
Formation of tropospheric ozone mostly occurs when nitrogen oxides (NOx), carbon monoxide (CO) and volatile organic compounds (VOCs) react in the atmosphere in the presence of sunlight. NOx, CO, and VOCs are therefore called ozone precursors. Apart from a health hazard, tropospheric ozone is an important greenhouse gas. Furthermore, carbon monoxide emissions contribute to hydroxyl depletion, thus extending the lifetime of methane.

While there appears to be little or no carbon dioxide from wildfires over North America on the above August 7 image, there are many recent wildfires raging over the North American continent, as illustrated by the August 12 map below, from Wunderground

[ click on image to enlarge ]
This point is illustrated even better on the image below [added later, ed.] showing a composite image with carbon monoxide over July 3-13, 2013. Carbon monoxide resulting from wildfires in Canada is seen crossing the Atlantic Ocean, due to the Coriolis effect, as well as reaching Greenland in large amounts.

[ click on image to enlarge ]


Related

- Wildfires even more damaging
http://arctic-news.blogspot.com/2013/07/wildfires-even-more-damaging.html

- The Threat of Wildfires in the North
http://arctic-news.blogspot.com/2013/06/the-threat-of-wildfires-in-the-north.html

- Wildfires in Canada affect the Arctic
http://arctic-news.blogspot.com/2013/07/wildfires-in-canada-affect-the-arctic.html

Cyclone raging on Thin Ice

Another cyclone is raging over the Arctic Ocean. The Naval Research Laboratory image below shows the speed and drift of the sea ice.

[ click on image to enlarge ]
Last time a cyclone hit the Arctic, this resulted in a temporary increase in area covered by sea ice, as shown on the Cryosphere Today image below. The cyclone pushed down on the sea ice, flattening it and pushing it sideways. 


Note that area as measured by the Cryosphere Today includes all spots that have a 15% or higher concentration of ice. This way of measuring area ignores the fact that the cyclone reduced the sea ice concentration in many spots, from a high sea ice concentration (around 90%) to a lower concentration (less than 80%), as shown on the Naval Research Laboratory image below. 


Furthermore, sea ice has since dropped in thickness, as illustrated by the Naval Research Laboratory image below. 

Much of the ice is now less than one meter thick, while some areas close to the North Pole have ice that is only between zero and half a meter thick.

The cyclone is raging most fiercely in those areas and much of the ice is drifting out into the Atlantic Ocean.

Neven mentioned at the Arctic Sea Ice Blog that average thickness (crudely calculated by dividing PIOMAS (PI) volume numbers with Cryosphere Today (CT) sea ice area numbers, see image below) had a very steep drop in July, similar to the drop in 2010. This year's trend line is now lowest, probably signifying that the ice pack is spread out and thin at the edges (read: melting potential).

[ click on image to enlarge ]
The image below, from the University of Bremen, Germany, shows sea ice concentration on August 11, 2013.



Arctic satellite thermal infrared CH4 data compared to surface in-situ and total column measurements

Leonid Yurganov, Senior Research Scientist,
Joint Center for Earth Systems Technology,
University of Maryland Baltimore County


Below an abstract of a paper written by Leonid Yurganov, Xiaozhen Xiong and Ira Liefer, and submitted for presentation at the AGU-Fall meeting 2013.

ABSTRACT: The trace gas sensitivity of Thermal InfraRed (TIR) sounders (AIRS, IASI, TANSO) is greatest in the middle and upper troposphere; though, lower troposphere (1-2 km of altitude) sensitivity is less but not negligible. As a result, where methane largely is constrained to the lower troposphere, as is common in the Arctic particularly the marine Arctic, retrievals from these instruments provides important synoptic data on high latitude methane sources. Low Arctic water vapor content favors a better sensitivity to methane as well: H2O is the main absorber in the 7.8 micrometers spectral region.

Both AIRS/Aqua v6 (NASA) and IASI/Metop-A (NOAA/NESDIS/CLASS retrievals) methane data averaged over 0-4 km altitude clearly demonstrate increased methane concentrations over the Barents and Norwegian Seas (BNS) with seasonal maximum in December - March. Similar increases are observed over the Kara, Laptev, and Chukchi Seas for September-November, i.e. during the period of minimum ice cover over the Arctic (Figures 1 and 2). Comparison of a long series of AIRS data with in situ methane concentrations at the Zeppelin NILU observatory (Svalbard) show good agreement both in amplitude and phase of seasonal variations. Agreement with Barrow NOAA continuous methane in situ data is much worse, which likely results from lower thermal contrast in winter over the cold and icy surfaces of the Eastern Arctic. Further surface validation is by a comparison of total methane columns with the Sun-Tracking FTIR at Ny-Alesund, Svalbard (TCCON network).

These analyses demonstrate that TIR satellites are capable of detecting Arctic methane enhancements from space, particularly over relatively warm year-round water surfaces such as the BNS. Ongoing research is addressing further verification of retrieved methane columns by collecting data with a cavity ring-down spectroscopy analyzer for methane and carbon dioxide on board of the Russian Research Vessel Akademik Fedorov during the expedition NABOS-2013. Data will be collected to measure marine methane concentrations and vertical fluxes between Norway and the Eastern Arctic (New Siberian Islands) between 20 August and 23 September, 2013.

Figure 1

Figure 2. methane concentrations over the Barents and Norwegian Seas (BNS), over the Kara, Laptev, and East Siberian Seas, and over Eurasia (between 50 and 70 degrees North)

Sunday, August 11, 2013

Dramatic rise in methane levels since end July 2013

There has been a dramatic rise in methane levels since end July 2013. The image below pictures methane levels above 1950 ppb on the Northern Hemisphere from 12 p.m. August 9, 2013, to 12 a.m. August 10, 2013.


[ click on image to enlarge ]
Quite suddenly, readings above 1950 ppb have become commonplace since July 31, 2013.


The chart below illustrates the dramatic jump in methane levels that occurred since July 31, 2013. The chart shows the area (square km) with methane readings over 1950 ppb for selected layers, over the period from July 24, 2013, to August 9, 2013. The chart further below shows that peak methane levels have increased dramatically.

Particularly worrying are high levels of methane over the Arctic Ocean, such as on the image below showing methane levels over 1950 ppb in yellow for selected layers on August 5, 2013 (a.m.).
[ click on image to enlarge ]
Methane levels are also very high on the Southern Hemisphere, as illustrated by the image below on the right. High readings have featured over the heights of Antarctica for quite some time, but the high levels of methane over the oceans on the Southern Hemisphere have only shown up recently. They could be caused by one or more methane hydrates getting destabilized in the ocean between Antarctica and South America.
[ click on image to enlarge ]
Peter Carter sent the image below, edited from NOAA Earth System Research Laboratory, showing high (and rising) methane levels in Pallas Sammaltunturi (north Scandinavia), measured with surface flasks.

Peter also added the image below, pointing at high methane levels in Lac La Biche, Northern Alberta, Canada. What to make of it?, Peter adds, It is not far from the Tar Sands - that does have a methane problem, but it is basically wetland peat region vicinity which is why I checked it.

Friday, August 9, 2013

Methane levels remain very high around the globe

The image below shows methane levels over 1950 in yellow for both hemispheres, on the morning of August 8, 2013.

[ click on image to enlarge ]
The highest peak recorded was 2428 ppb at 367 mb. The highest mean was 1822 ppb at 469 mb. See also the image below for an overview of recent methane levels.

for interactive version, see http://arctic-news.blogspot.com/2013/08/methane-levels-keep-rising-rapidly.html
The situation is very worrying, especially since there's a huge amount of methane in the northern part of Asia and Europe, much of it bordering on the Arctic. This methane will trap a lot of heat there at a time when the melting season is still going strong.

On the Southern Hemisphere, there's a huge amount of methane recorded over Antarctica. That has been going on for quite some time, but the high levels of methane over the oceans on the Southern Hemisphere have only shown up recently. They could be caused by one or more methane hydrates getting destabilized in the ocean between Antarctica and South America.