Showing posts with label SST. Show all posts
Showing posts with label SST. Show all posts

Thursday, May 21, 2015

Arctic Sea Ice At Historic Low

On May 20, 2015, Arctic sea ice extent was only 12.425 million square km, a record low for the time of the year since satellite measurements began in 1979.


As the Arctic Sea Ice is at a historic low, Alaska faces temperatures as high as 31°C (87.8°F), as illustrated by the image below.



How is it possible for temperatures to get so high at locations so close to the North Pole?

Typhoon Dolphin
Dr. Michael Ventrice, Operational Scientist at The Weather Channel Professional Division points at two typhoons, Noul and Dolphin, that recently hit the western Pacific Ocean.

These typhoons do have some impact. Importantly, global warming is increasing the strength of cyclones. In other words, a greater impact of cyclones on the jet stream can be expected as a feedback of global warming.

Furthermore, global warming is directly changing the path followed by the North Polar Jet Stream, from a relatively straight path at a latitude of 60°N to a wildly meandering path that at some places merges with the Subtropical Jet Stream and reaching speeds as high as 267 km/h (166 mph) and that at other places moves high into the Arctic and reaches speeds as high as 170 km/h (106 mph).



On above image, part of the jet stream even moves right across the pole. Such changes to the jet stream constitute one out of numerous feedbacks of global warming, as discussed at the feedbacks page. Decline of the snow cover and sea ice in the Arctic is another such feedback.

As discussed in earlier posts, heat waves at high latitudes cause thawing of frozen soil and melting of glaciers and snow cover, This results in large amounts of water draining into rivers that end up in the Arctic Ocean. At the same time, heat waves also raise the temperature of the water in these rivers. The larger amounts of warmer water result in additional sea ice decline and warming of the Arctic Ocean seabed.

Such heat waves also set the scene for wildfires that emit not only greenhouse gases such as carbon dioxide and methane, but also pollutants such as carbon monoxide (that depletes hydroxyl that could otherwise break down methane) and black carbon (that when settling on ice causes it to absorb more sunlight).


Above image shows how much warmer the water in the Arctic Ocean is compared to what it used to be, with high anomalies where rivers flow into the Arctic Ocean and where the Gulf Stream carries warm water from the Atlantic Ocean into the Arctic Ocean.

The situation looks set to get worse, as the frequency and intensity of heat waves in North America and Siberia increases as temperature at high latitudes are rising rapidly. Furthermore, warm water is lining up along the path of the Gulf Stream, with sea surface temperature anomalies as high as 10.3°C (18.54°F) recorded off the coast of North America on May 20, 2015, as illustrated by the image below.

Green circle shows a 10.3°C (18.54°F) sea surface temperature anomaly from daily average (1981-2011)

Meanwhile, a very high methane reading was recorded at Barrow, Alaska (hourly average, in situ measurement), as illustrated by the image below.


The big danger is that the combined impact of these feedbacks will accelerate warming in the Arctic to a point where huge amounts of methane will erupt abruptly from the seafloor of the Arctic Ocean.

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



As the Arctic Sea Ice is at a historic low, Alaska faces temperatures as high as 31°C (87.8°F). From the post: Arctic...
Posted by Sam Carana on Thursday, May 21, 2015

Friday, March 6, 2015

March 4, 2015 - Arctic Sea Ice Extent Hits Record Low

Sea surface temperature anomalies as high as 12°C (21.6°F) recorded off the east coast of North America have been described earlier, in he post 'Watch where the wind blows'. The Jet Stream reaching high speeds has also been described earlier, in the post 'Climate Changed'.


As feared, this is pushing warm water, water vapor and air from the North Atlantic into the Arctic Ocean. The three images below show forecasts for March 8, 2015, of - from top to bottom - the jet stream, surface winds and temperature anomalies.





Above image shows that the Arctic is forecast to reach a temperature anomaly of more than +4 degrees Celsius (more than +7 degrees Fahrenheit) on March 8, 2015, with temperature anomalies at the top end of the scale forecast for most of the Arctic Ocean.

On March 4, 2015, Arctic sea ice extent hit a record low for the time of the year, as illustrated by the image below.


As the March 5, 2015, Naval Research Laboratory image on the right illustrates, there is little scope for Arctic sea ice extent to grow over the next few weeks, since the only areas where it could possibly expand would be the Pacific and the North Atlantic, the very areas that are under pressure from ocean heat and high surface temperatures.

In other words, the situation looks set to deteriorate further.

Huge amounts of heat are still going into melting the sea ice. Furthermore, the sea ice is still able to reflect a lot of sunlight back into space. With continued demise of the snow and ice cover, more and more heat will be absorbed in the Arctic.

The big danger is that warm water will trigger further releases of methane from the seafloor of the Arctic Ocean. Peak daily methane levels recorded in early 2015 averaged a very high 2372 parts per billion, as illustrated by the image below.


Methane extent has been especially high over the Arctic Ocean. The images below are from the earlier post 'Temperature Rise'. The post added that, as the Gulf Stream keeps carrying ever warmer water into the Arctic Ocean, methane gets released in large quantities, as illustrated by the images below showing high methane levels over the East Siberian Arctic Shelf (red oval left) and over Baffin Bay (red oval right) with concentrations as high as 2619 ppb.

click on image to enlarge
The images below show methane levels on Jan 25 (top), and Jan 26, 2015 (bottom).


Update:
Meanwhile, Arctic sea ice extent as reported by NSIDC.org reached a new record low for the time of the year with 14.358 million square km on March 4, 2015, and another record low with 14.308 million square km on March 7, 2015.

Temperature anomaly for the Arctic on March 8, 2015 (daily average) was even higher tha forecast, at +4.26 degrees Celsius, with peaks at +4.37 degrees Celsius.



High waves were registered in the North Atlantic on March 7, 2015, moving into the Arctic Ocean and causing waves more than 4 m high close to the edge of the sea ice on March 8, 2015.



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


Saturday, October 4, 2014

Record June–August Global Ocean Surface Temperature

August 2014 record high land and ocean temperature

The combined average temperature across global land and ocean surfaces for August 2014 was record high for the month, at 0.75°C (1.35°F) above the 20th century average of 15.6°C (60.1°F).

June–August 2014 record high land and ocean temperature

June–August 2014, at 0.71°C (1.28°F) higher than the 20th century average, was the warmest such period across global land and ocean surfaces since record keeping began in 1880.

August 2014 record high sea surface temperature

The August global sea surface temperature (SST) was 0.65°C (1.17°F) above the 20th century average of 16.4°C (61.4°F). This record high departure from average not only beats the previous August record set in 2005 by 0.08°C (0.14°F), but also beats the previous all-time record set just two months ago in June 2014 by 0.03°C (0.05°F).

June–August 2014 record high sea surface temperature

The June–August global ocean surface temperature was 0.63°C (1.13°F) above the 20th century average, the highest on record for June–August. This beats the previous record set in 2009 by 0.04°C (0.07°F).


John Davies comments: 

This was the warmest August on record, primarily due to very high Sea Surface Temperatures in the Northern Hemisphere.

There is no El Nino event in this period, but some sort of event - hopefully an event not a climate shift - is taking place. If this is an event, the situation will become more normal when it ends, which will be in less than a years time at worst. If it is a climate shift, we are in desperate trouble, though I think it is an event.

It is worth noting that these very high Sea Surface Temperatures are likely to lead to high land temperatures soon, as normally land temperatures in the Northern hemisphere can be expected to exceed Sea Surface Temperatures.

The drought affecting California and the whole of the west of North America, Central America, and large parts of the Brazilian rainforest, though preceding this event was almost certainly down to changes which started before this event but ultimately caused it.


Despite the record high combined average temperature across global land and ocean surfaces for August, the global economy will continue as normal and no specific action can be expected to be taken to curb emissions. This will change, if global temperatures continue to rise. Temperatures are high enough to cause global concern, however. More later.


Note: NOAA's most recent (Sep 4, 2014) prediction puts the chance of El Niño at 60-65% during the Northern Hemisphere fall and winter.





Sea surface temperatures (SST) can be expected to remain high in the Arctic Ocean, as SST anomalies are high in the North Atlantic (+1.65°C, image left) and high temperatures are forecast over the Arctic for at least the next seven days (anomalies as high as +2.87°C, image right). For a comparison with October 3 temperatures, see this earlier post.

Additionally, an increasing amount of heat has been going into the deeper parts of the ocean, and the Gulf Stream will for month to come continue to transport water into the Arctic Ocean, and this water will be warmer than the water already there, threatening to unleash ever larger eruptions of methane from the seafloor of the Arctic Ocean, as discussed in this earlier post.

In conclusion, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.


References

- NOAA National Climatic Data Center, State of the Climate: Global Analysis for August 2014.
http://www.ncdc.noaa.gov/sotc/global/2014/8

- EL NIÑO/SOUTHERN OSCILLATION (ENSO) DIAGNOSTIC DISCUSSION, issued by:
Climate Prediction Center/NCEP/NWS and the International Research Institute for Climate and Society, 4 September 2014
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.pdf

- ENSO: Recent Evolution, Current Status and Predictions
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

- ClimateReanalyzer.org
http://climatereanalyzer.org





Tuesday, September 30, 2014

Warm water extends from Laptev Sea to North Pole

The NOAA NESDIS image below shows sea surface temperature anomalies of well over 1ºC extending to the North Pole.


The image below gives a world view, showing SST anomalies at the top end of the scale in the Laptev Sea.


The top end of the scale on the above image is 5ºC (or 9ºF).



The visualizations above and below uses a much higher scale. Even this higher-end scale doesn't appear to fully capture the dire situation we are in.


Above image shows warm water entering the Arctic Ocean through the Bering Strait and from the North Atlantic. For months to come, the Gulf Stream will keep pushing warm water into the Arctic Ocean (i.e. water that is warmer than the water in the Arctic Ocean). It takes some time (i.e. months) for the warm water from the north Atlantic to arrive in the Arctic Ocean.

Last year, methane emissions started to become huge in October and this lasted for some six months. The image below, from an earlier post, shows methane eruptions from the seafloor of the Arctic Ocean on October 16/17, 2013.


The image below, from another earlier post, shows methane eruptions from the seafloor of the Arctic Ocean on October 31, 2013.


The image below, from yet another earlier post, shows methane levels as high as 2662 parts per billion on November 9, 2013.


This year, there is even more ocean heat present, especially in the north Atlantic and the north Pacific. On September 29, 2014, methane levels as high as 2641 parts per billion were recorded and it looks like worse is yet to come.


The video below, Sea floor methane hydrate climate hazard, is an extract produced by Peter Carter from a presentation by Miriam Kastner, uploaded 7 August 2008 at Youtube.



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


Saturday, August 30, 2014

Warming waters threaten to trigger methane eruptions from Arctic Ocean seafloor


K. Tung / Univ. of Washington. (Top) Global
average surface temperatures, where black dots
are yearly averages. Two flat periods (hiatus)
are separated by rapid warming from 1976-1999.
(Middle) Observations of heat content, compared
to the average, in the north Atlantic Ocean.
(Bottom) Salinity of the seawater in the same
part of the Atlantic. Higher salinity is seen
to coincide with more ocean heat storage.
A new study looks at how, in the 21st century, surface warming slowed as more heat moved deeper into the oceans, specifically the North Atlantic.

Sun-warmed salty water travels north along ocean currents in the Atlantic. When this saltier water reaches the North Atlantic, its greater density causes it to sink. From about 1999, this current began to speed up and draw heat deeper into the ocean.

These huge amounts of heat moving deeper into the Atlantic Ocean are very worrying.

The image below shows that sea surface temperatures have reached extremely high levels on the Northern Hemisphere, where sea surface temperature anomalies as high as 1.78 degrees Celsius were recorded on August 19, 2014.

As discussed in an earlier post, water carried by the Gulf Stream below the surface can be even warmer than surface waters. As the post discusses, high sea surface temperatures west of Svalbard indicate that the Gulf Stream can carry very warm water (warmer than 16°C) at greater depths and is pushing this underneath the sea ice north of Svalbard. Similarly, warm water from greater depth comes to the surface where the Gulf Stream pushes it against the west coast of Novaya Zemlya.


Very warm water is now invading the Arctic Ocean through the Bering Strait from the Pacific Ocean, while very warm water is also traveling on the back of the Gulf Stream from the North Atlantic into the Arctic Ocean.


The danger is that this warm water will destabilize hydrates contained in sediments under the Arctic Ocean and trigger huge methane eruptions.

Rising methane levels over the past few years are ominous in this respect. The image below shows very high mean global methane levels on August 28, 2014, while methane readings as high as 2561 ppb were recorded on that day.

Methane Levels -  see earlier post for a discussion of IPCC/NOAA data

In conclusion, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.



References and Related Links

- Varying planetary heat sink led to global-warming slowdown and acceleration
by Xianyao Chen and Ka-Kit Tung.
http://www.sciencemag.org/content/345/6199/897

- Cause of global warming hiatus found deep in the Atlantic Ocean
University of Washington News Release
http://www.washington.edu/news/2014/08/21/cause-of-global-warming-hiatus-found-deep-in-the-atlantic-ocean

- Horrific Methane Eruptions in East Siberian Sea
http://arctic-news.blogspot.com/2014/08/horrific-methane-eruptions-in-east-siberian-sea.html

- Methane Buildup in the Atmosphere
http://arctic-news.blogspot.com/2014/04/methane-buildup-in-atmosphere.html

- Climate Plan blog
http://climateplan.blogspot.com



Tuesday, August 19, 2014

Persistently High Methane Concentrations over Beaufort Sea

High methane concentrations have been showing up over Beaufort Sea over the past few days, as shown on the image below. This follows the recent high methane concentrations over the East Siberian Sea.


The persistent character of these very high methane concentrations over the Arctic Ocean indicates that methane has started to erupt from clathrates under the seabed, triggered by very warm water reaching the bottom of the Arctic Ocean.

Methane eruptions from hydrates in sediments under the Arctic Ocean helped mean methane levels reach new records, with mean global methane readings as high as 1835 parts per billion recorded at several altitudes on August 17, 2014.


The very high sea surface temperature anomalies that show up on above image give an idea of the inflow of warm water from the Pacific Ocean through the Bering Strait. This is further highlighted by the combination image below.

[ click on image to enlarge ]
The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.


Monday, August 4, 2014

Warm waters threaten to trigger huge methane eruptions from Arctic Ocean seafloor

The evidence of abrupt high methane releases in the Arctic Ocean is accumulating. The graph below shows in situ methane measurements taken at the Barrow Observatory, including recent levels as high as close to 2200 parts per billion (ppb).


Satellite data picture a similarly dire situation. Global mean methane levels as high as 1831 ppb were recorded on the morning of July 30, 2014, while peak methane levels as high as 2330 ppb were recorded that morning. More recently, peak methane levels as high as 2522 ppb were recorded (on August 2, 2014).

IPCC/NOAA figures suggest that methane levels were rising by some 5 to 6 ppb annually, reaching 1814 ppb in 2013. While methane levels at lower altitudes have indeed shown little rise, much larger rises have been recorded at higher altitudes, as illustrated by the image below.


These high methane levels recorded at higher altitudes appear to be caused by the huge quantities of methane released from the seafloor of the Arctic Ocean during the period from end 2013 to early 2014. This methane has meanwhile risen to higher altitudes, while also descending to lower latitudes, wreaking havoc on weather patterns around latitude 60° North.

The releases of methane from the seafloor of the Arctic Ocean were caused by water that had warmed up strongly off the east coast of North America from June 2013. It took some months for this warm water to be carried by the Gulf Stream into the Arctic Ocean.


Meanwhile, very high sea surface temperatures are recorded in the Arctic Ocean, as above image shows, while warm water is carried into the Arctic Ocean by the Gulf Stream, as illustrated by the image below.


As said, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.




Friday, July 4, 2014

The Threat of Storms Wreaking Havoc in the Arctic Ocean

Arctic sea ice extent is close to a record low for the time of the year, as the image below shows.


Furthermore, the current decline in sea ice extent is much steeper than it used to be for this time of the year, raising the specter of sea ice hitting an absolute record low later this year. Moreover, a total collapse of sea ice may occur if storms continue to develop that push the remaining ice out of the Arctic Ocean into the Atlantic Ocean.


The threat posed by storms is illustrated by the track projected to be followed by Hurricane Arthur (above NOAA image, July 4), renamed as Post-Tropical Cyclone Arthur (NOAA image below, July 5).



The path followed by Arthur is influenced by the current shape of the jet stream. As the animation below illustrates, the jet stream looks set to prevent Hurrican Arthur from moving to the east and instead make it move into the Labrador Sea to the west of Greenland and - partly due to the high mountains on Greenland - continue to wreak havoc in Baffin Bay further north.

[ Note: this animation is a 1.87 MB file that may take some time to fully load ]
As described in an earlier post, post-tropical cyclone Leslie made landfall with hurricane-force winds in Newfoundland in September 2012. The large extratropical low pressure system continued to move rapidly northeastward across eastern Newfoundland at a forward speed of near 45 kt, and merged with a much larger extratropical low over the Labrador Sea.

Recent research by NOAA-affiliated scientists suggests that - over the years - the latitude where hurricanes, typhoons, and cyclones reach their maximum intensity on the Northern Hemisphere has shifted closer to the North Pole.

Such storms can bring lots of heat and moisture into the Arctic, and they can also increase the height of waves. All this can have devastating impact on the sea ice. The many ways in which storms can increase the dangerous situation in the Arctic is described in the post Feedbacks in the Arctic.

Last month, the June heat record broke in Greenland. Very high temperatures are currently recorded all over North America, as the image below shows.


Furthermore, sea surface temperature anomalies in the Arctic are currently very high, as the image below shows.


Additionally, the sea ice is currently very thin, as shown by the Naval Research Laboratory animation below.


The above animation further shows that there now is very little sea ice left in Baffin Bay, making it easier for storms to cause very high waves that could enter the Arctic Ocean and break the sea ice north of Greenland and Canada.

Arctic sea ice volume minimum is typically reached around halfway into September. This is still months away, but the prospect of an El Niño event striking this year now is 90%, according to predictions by the European Centre for Medium-range Weather Forecasts.

All this combines into a growing threat that hydrates contained in sediments will destabilize and that huge quantities of methane will be released abruptly from the seafloor of the Arctic Ocean. The risk that this will eventuate is intolerable and calls for parallel lines of action as pictured in the image below.

Climate Plan, July 7, 2014 version, as discussed at this Climate Plan post and at the Climate Plan blog

Related

- Storm enters Arctic region
arctic-news.blogspot.com/2012/09/storm-enters-arctic-region.html

- Huge cyclone batters Arctic sea ice
arctic-news.blogspot.com/2012/08/huge-cyclone-batters-arctic-sea-ice.html

- Hurricane Sandy moving inland
http://arctic-news.blogspot.com/2012/10/hurricane-sandy-moving-inland.html

- Feedbacks in the Arctic
http://arctic-news.blogspot.com/2014/03/feedbacks-in-the-artcic.html



Wednesday, July 2, 2014

What's wrong with the weather?


Above map shows temperatures in NewFoundland and Labrador close to 30°C (86°F), compared to temperatures in Albuquerque, New Mexico of only 20°C (68°F), while temperatures seem to be even lower in Mexico City. What's happening with the weather?

Jet Streams are changing


World climate zones used to be kept well apart by jet streams. On the northern hemisphere, the polar jet stream was working hard to separate the Tundra and Boreal climate zones' colder air in the north from the Temperate climate and the Subtropical climate zones' warmer air in the south.

As the Arctic is warming even faster than the Equator, the falling temperature difference between the two reduces the speed at which warm air is moving from the Equator to the North Pole. This in turn slows the speed at which the jet streams are circumnavigating the globe on the Northern hemisphere and it is deforming the jet streams in other ways as well.

NOAA image ]
As above image shows, the polar jet stream is typically located at about 60°N and the subtropical jet stream at about 30°N. The polar jet stream's altitude typically is near the 250 hPa pressure level, or 7 to 12 kilometres (4.3 to 7.5 mi) above sea level, while the weaker subtropical jet stream's altitude is higher, between 10 and 16 kilometres (6.2 and 9.9 mi) above sea level.

NOAA image
The polar jet stream used to travel at speeds of up to 140 miles per hour, while following a relatively straight track that was meandering only slightly, i.e. with waves that go up and down only a little bit. This fast and relatively straight jet stream kept climate zones well apart. Accordingly, the Northern Temperate Zone used to experience only mild differences between summer and winter weather, rather than the extremely hot or cold temperatures that we're increasingly experiencing now.

Polar jet stream (blue) & subtropical
jet stream (red) - NOAA image
Loss of snow and ice cover in the north is accelerating warming in the Arctic. This is decreasing the difference in temperature between the Arctic and the Northern Temperate Zone, in turn causing the polar jet to slow down and become more wavy, i.e. with larger loops, as illustrated by the animation below.

Imagine a river that at first rapidly runs down a narrow and straight path when its waters fall down from the top of a high mountain. Once that river flows through flat land, though, it becomes slow and curvy.

Similarly, the polar jet stream is now circumnavigating the globe at slower speed and along a wavier tracks. Its waves are now more elongated, more stretched out vertically, making that cold air can move more easily down from the Arctic, e.g. through the middle of North America, as illustrated by the animation below.

At the same time, warm air can move up more easily from the South into the Arctic. This is creating huge temperature anomalies in many places, as also illustrated by the animation below.