Showing posts with label anomaly. Show all posts
Showing posts with label anomaly. Show all posts

Friday 21 August 2015

Ocean Heat Invades Arctic Ocean

[ click on image to enlarge ]
NOAA analysis shows that, on land, it now is about 1°C (1.8°F) warmer than the 20th century average.

July 2015 was the warmest month ever recorded for the globe. The combined average temperature over global land and ocean surfaces for July was the all-time highest monthly temperature in the 1880-2015 record – it was 16.61°C (61.86°F), i.e. 0.81°C (1.46°F) above the 20th century average. 

Sea surfaces were very warm as well, in particular the North Pacific, which on August 22, 2015, was exactly 1°C (1.8°F) warmer than it was compared to the period from 1971 to 2000 (see Climate Reanalyzer image right).

The July globally-averaged sea surface temperature was the highest temperature for any month in the 1880-2015 record. In July 2015, the sea surface on the Northern Hemisphere was 0.87°C (1.57°F) warmer than it was in the 20th century, as illustrated by the NOAA graph below. 



As the image below shows, the July data for sea surface temperature anomalies on the Northern Hemisphere contain a trendline pointing at a rise of 2°C (3.6°F) before the year 2030. In other words, if this trend continues, the sea surface will be 2°C (3.6°F) warmer in less than 15 years time from now.

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Such a temperature rise would be a catastrophe, as there are huge amounts of methane contained in the form of hydrates and free gas in sediments under the Arctic Ocean seafloor. A relatively small temperature rise of part of these sediments could cause a huge abrupt methane eruption, which could in turn trigger further eruptions of methane.

As illustrated by the image below, high methane levels are already showing up over the Arctic.

Methane levels as high as 2565 parts per billion were recorded on August 18, 2015

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Loss of Arctic sea ice could speed up such a development. The image on the right shows that, on August 20, 2015, Arctic sea ice extent was at a record low for the time of the year except for the years 2007, 2011 and 2012.

The situation today is even worse than one might conclude when looking at sea ice extent alone. Thick sea ice is virtually absent compared to the situation in the year 2012 around this time of year, as illustrated by the image below that compares sea ice thickness on August 20, 2012 (left) with August 20, 2015 (right).


The comparison below further illustrates this. The left panel shows how thick sea ice is anchored to the north-east tip of Greenland on July 7, 2015. The right panel shows how, on August 20, 2015, this ice has been fractured and shattered into pieces. All this ice looks set to soon flow down Fram Strait and melt away in ever warmer water.


The image below shows sea surface temperature anomalies on August 21, 2015.


On the image below, the green circle at the top of each globe indicates a location where sea surface temperature was 17°C (62.6°F) on August 21, 2015, an anomaly of 11.9°C (21.4°F). This is where warm water is entering the Arctic Ocean from the Atlantic Ocean. At the same time, warm water is entering the Arctic ocean through the Bering Strait from the Pacific Ocean.

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There still are a few weeks to go before sea ice can be expected to reach its minimum, at around half September 2015, while sea currents will continue to carry warmer water into the Arctic Ocean for months to come. More open water increases the chance that storms will develop that will push the last remnants of the sea ice out of the Arctic Ocean, as discussed in earlier posts such as this one, while storms can also mix warm surface waters all the way down to the seafloor, as discussed in this earlier post.

Typhoons increase this danger. The Climate Reanalyzer image below shows typhoons in the Pacific.


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Typhoons developing in the Pacific Ocean are getting stronger as the oceans warm. One of the typhoons visible on above map, Typhoon Goni, has just claimed ten lives in the Philippines.

Stronger typhoons come with an increased chance that they will bring strong winds and warm air and water into the Arctic.

Typhoon Goni and the larger Typhoon Atsani are both moving north and look set to move into the direction of the Arctic Ocean, as illustrated by the forecast for the situation on August 26, 2015, on the right.

Atsani was the twelfth typhoon and sixth super typhoon of the year in the western North Pacific—numbers that meteorologists say put the season on a record-breaking track. The NASA image below gives an idea of the size of Typhoon Atsani.

[ Typhoon Atsani - NASA image ]
The situation is dire and calls for comprehensive and effective action, as discussed in the Climate Plan.


July data for sea surface temperature anomalies on the Northern Hemisphere contain a trendline pointing at a rise of 2°C...
Posted by Sam Carana on Friday, August 21, 2015

Friday 7 August 2015

Record High Methane Levels

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As the top image shows, sea surface temperature anomalies in the Bering Strait on August 4, 2015, were as high as 8.7°C (15.6°F). Such high anomalies are caused by a combination of ocean heat, of heatwaves over Alaska and Siberia extending over the Bering Strait, and of warm river water run-off.

As the image on the right shows, sea surface temperatures in the Bering Strait were as high as 20.5°C (69.1°F) on August 4, 2015.

As warm water flows through the Bering Strait into the Arctic Ocean, it dives under the sea ice and becomes harder to detect by satellites that typically measure water temperatures at the surface, rather than below the surface.

The image below shows sea surface temperature anomalies from 1971 to 2000, for August 6, 2015, as visualized by Climate Reanalyzer.


Climate Reanalyzer applies a mask over sea-ice-covered gridcells, reducing anomalies in such cells to zero.

Below is a NOAA image, for August 5, 2015, also with anomalies from 1971 to 2000.


Below is another NOAA image, showing anomalies for August 6, 2015. Because the base period is 1961 to 1990, the anomalies are higher. Nonetheless, the yellow areas that feature around the North Pole on above image do not show up on the image below.


In other words, looking at sea surface temperatures alone may lead to underestimations of the temperatures of the water underneath the sea ice. Keeping that in mind, have a look again at the high anomalies on the image below.


The danger is that further decline of the sea ice will lead to rapid warming of the Arctic Ocean, while the presence of more open water will also increase the opportunity for strong storms to develop that can mix high sea surface temperatures all the way down to the seafloor, resulting in destabilization of sediments and triggering releases of methane that can be contained in such sediments in huge amounts.

The image below shows that global mean methane levels as high as 1840 parts per billion (ppb) were recorded on August 4, 2015. Peak methane levels that day were as high as 2477 ppb.


This peak level of 2477 ppb isn't the highest recorded the year. As the image below shows and as discussed in a previous post, methane levels as high as 2845 ppb were recorded on April 25, 2015. The average of the daily peaks for this year up to now is 2355 ppb. Very worrying about the above image are the high levels of methane showing up over the Arctic Ocean.


As above image also shows, the mean methane level of 1840 ppb is in line with expectations, as methane levels rise over the course of the year, to reach a maximum in September. This mean level of 1840 ppb is higher than any mean level since records began.

The image below shows all the World Meteorological Organisation (WMO) annual means that are available, i.e. for the period 1984 through to 2013.


As above image shows, a polynomial trendline based on these WMO data (for the period 1984 through to 2013) points at a doubling of mean global methane levels by about 2040. The added NOAA data are the highest mean in 2014, i.e. 1839 ppb recorded on September 7, 2014, and the above-mentioned level of 1840 ppb recorded on August 4, 2015.

As said, mean global methane levels last year reached its peak in September and the same is likely to occur this year. In other words, this new record is likely to be superseded by even higher levels soon.

The image on the right shows the steady rise of the highest mean daily methane levels that have been recorded recently, indicating that a continued rise can be expected that would put another highest mean level for 2015 on the trendline of above image soon.

Again, the danger is that a warming Arctic Ocean will trigger further methane releases from the seafloor, leading to rapid local warming that in turn will trigger further methane releases, in a vicious cycle of runway warming.

As illustrated by the image on the right, at a 10-year timescale, the current global release of methane from all anthropogenic sources exceeds all anthropogenic carbon dioxide emissions as agents of global warming.

Over the next decade or so, methane emissions are already now more important than carbon dioxide emissions in driving the rate of global warming, and this situation looks set to get worse fast.

Unlike carbon dioxide, methane's GWP does rise as more of it is released. Higher methane levels cause depletion of hydroxyl, which is the main way for methane to be broken down in the atmosphere.

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



The image shows all the World Meteorological Organisation (WMO) annual means that are available, i.e. for the period...
Posted by Sam Carana on Friday, August 7, 2015

Tuesday 21 July 2015

Ocean Temperatures At Record High

Of all the excess heat that results from people's emissions, 93.4% goes into oceans. Accordingly, ocean heat has strongly increased over the years.

NOAA analysis shows that, for the oceans on the Northern Hemisphere, the June 2015 sea surface temperature was at a record high 0.87°C (1.57°F) above the 20th century average of 16.4°C (61.5°F), as also illustrated by the graph below.


The most recent 12-month period, July 2014–June 2015, also broke the record (set just last month) for the all-time warmest 12-month period in the 135-year period of record. 


As the above image shows, sea surface temperature anomalies around North America are very high, threatening to further raise temperatures of the Arctic Ocean, which already has very high sea surface temperatures, as also illustrated by the image below. 


As the image below shows, sea surface temperatures as high as 19°C (66.2°F) were recorded in the Bering Strait on July 19, 2015.



The snow depth comparison below shows the situation on July 20, 2015, on the left and a forecast for July 27, 2015, on the right. The green lines indicate areas where sea ice is at melting point. Note the decline of snow cover on Greenland and the Himalayas.


As the continued snow decline on Greenland also illustrates, high temperatures can be expected to keep causing further decline of the snow and ice cover for many weeks to come, given that the minimum sea ice extent is typically reached about half September.

As the image below shows, sea surface temperatures as high as 10.1°C (50.1°F) were recorded in Baffin Bay, off the west coast of Greenland, on July 20, 2015.


On July 21, 2015, temperatures as high as 14°C (57.1°F) were recorded east of Svalbard, an anomaly of 9.7°C (17.4°F), as illustrated by the image below, created with nullschool.net images.


The danger is that warm water will enter the Arctic Ocean and cause the Arctic sea ice to collapse, which could make the Arctic Ocean absorb even more heat. This could unleash huge methane eruptions from the Arctic Ocean's seafloor, in turn driving temperatures up even higher and causing more extreme weather events, wildfires, etc.

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



For the oceans on the Northern Hemisphere, the June 2015 sea surface temperature was at a record high 0.87°C (1.57°F)...
Posted by Sam Carana on Tuesday, July 21, 2015

Friday 27 March 2015

Methane Levels Early 2015


The image below shows highest mean methane readings on one day, i.e. March 10, compared between three years, i.e. 2013, 2014 and 2015, at selected altitudes. The comparison indicates that the increase of methane in the atmosphere is accelerating, especially at higher altitudes.


The table below shows the altitude equivalents in mb (millibar) and feet.

56925 feet44689 feet36850 feet30569 feet25543 feet19819 feet14383 feet8367 feet1916 feet
74 mb147 mb218 mb293 mb367 mb469 mb586 mb742 mb945 mb

This rise in global mean methane levels appears to go hand in hand with much higher peak readings, especially at higher altitudes.



From January 1 to March 20, 2015, methane levels reached levels as high as 2619 ppb (on January 12, 2015), while peak daily levels averaged 2373 parts per billion (ppb). At the start of the year, global mean methane levels typically reach their lowest point, while highest mean levels are typically reached in September. Highest daily global mean methane levels for the period from January 1, 2015, to March 20, 2015, ranged from 1807 ppb (January 6, 2015) to 1827 ppb (March 5, 2015).

Further study of the locations with high methane levels indicates that much of the additional methane appears to originate from releases at higher latitudes of the Northern Hemisphere, in particular from the Arctic Ocean, from where it is over time descending toward the equator (methane will typically move closer to the equator over time as it rises in altitude, as discussed in this earlier post).

The largest source of additional methane appears to be emissions from the seabed of the Arctic Ocean. Annual emissions from hydrates were estimated to amount to 99 Tg annually in a 2014  post (image below).





The image below, based on data from the IPCC and the World Metereological Organization (WMO), with an added observation from a NOAA MetOp satellite image, illustrates the recent rise of methane levels and the threat that methane levels will continue to rise rapidly.



What causes these methane eruptions?

Methane eruptions from the seafloor of the Arctic Ocean appear to be primarily caused by rising ocean heat that is carried by the Gulf Stream into the Arctic Ocean. The image below shows sea surface temperatures of 20.9°C (69.62°F, green circle left) recorded off the coast of North America on March 14, 2015, an anomaly of 12.3°C (36.54°F).

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Furthermore, both methane eruptions from the Arctic Ocean seafloor and demise of the Arctic sea ice and snow cover are feedbacks that can interact and amplify each other in non-linear ways, resulting in rapid and intense temperature rises, as illustrated by the image below.

Diagram of Doom - for more background, see Feedbacks
How high could temperatures rise?

Worryingly, a non-linear trend is also contained in the temperature data that NASA has gathered over the years, as described in an earlier post. A polynomial trendline points at global temperature anomalies of over 4°C by 2060. Even worse, a polynomial trend for the Arctic shows temperature anomalies of over 4°C by 2020, 6°C by 2030 and 15°C by 2050, threatening to cause major feedbacks to kick in, including albedo changes and methane releases that will trigger runaway global warming that looks set to eventually catch up with accelerated warming in the Arctic and result in global temperature anomalies of 16°C by 2052.

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Action

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




Comparison between three years, i.e. 2013, 2014 and 2015, of highest mean methane readings at selected altitudes on...
Posted by Sam Carana on Friday, March 27, 2015

Friday 6 March 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.

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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.


Monday 16 February 2015

Climate Changed

Our climate has changed, as illustrated by the image below (Forecast for Feb. 23, 2015, 1200 UTC, run on Feb. 16, 2015).


The left map shows temperatures of 40 degrees below zero moving down into North America from the Arctic, while temperatures in much of Alaska are above freezing point. The right map shows temperature anomalies over large parts of North America at both the top end (red) and the bottom end (purple) of the scale. Temperature anomaly forecasts for the week from Feb 19 to 26, 2015, feature in the video below.



Below is an update showing operational temperature anomalies recorded on February 23, 2015.


As parts of North America experienced record cold, part of Alaska was more than 20°C (36°F)
warmer than it used to be (compared to 1985-1996). And despite the cold weather in parts of Canada and Greenland, the Arctic as a whole is forecast to reach, on February 26, temperature anomalies as much as 3.32°C (6°F) above what temperatures used to be from 1979 to 2000 (Climate Reanalyzer forecast data).

What has caused our climate to change in this way? The image below shows that the jet stream, which once used to move over North America horizontally, has become more wavy, pushing warm air north on the left, while drawing cold air from the Arctic south on the right.


Importantly, while the jet stream is becoming more wavy or elongated vertically, the speed at which it crosses the oceans can increase dramatically. This can be the case where low temperatures over land and high sea surface temperatures combine to create huge temperature differences that drive up the jet stream's speed over oceans.

This is illustrated by the image below showing the Jet Stream reaching speeds as high as 410 km/h (or 255 mph) at the green circle near Greenland on January 9, 2015 (left), and speeds as high as 403 km/h (or 250 mph) at the green circle near Greenland on February 20, 2015 (right).


The reference map on the right shows the location of the continents for the same orthgraphic coordinates as the maps above and below.

Similarly, the Polar Vortex can reach high speeds, driving cold air downward over North America and driving warm air upward over Greenland and the North Atlantic.

The image below shows the Polar Vortex reaching speeds as high as 346 km/h (or 215 mph) at the green circle near Svalbard on January 18, 2015 (left), and speeds as high as 316 km/h (or 196.4 mph) at the green circle over the Arctic Ocean on February 9, 2015 (right).


Almost one year ago, the Polar Vortex also reached speeds as high as 410 km/h (or 255 mph), as discussed in an earlier post. Changes to the polar vortex and the jet stream are caused by emissions, and the situation looks set to deteriorate even further.


Above image illustrates that, on February 16, 2015, waves higher than 10 m (32.81 ft) were recorded off the east coast of North America and south of Iceland, while waves as high as 8.15 m (26.74 ft) were recorded in between Norway and Svalbard.

As above images also illustrate, changed wind patterns are carrying warm air high up into the Arctic.

The air that is moving north is much warmer than it used to be, as sea surface temperatures off the east coast of North America are much higher than they used to be (image left and as discussed in an earlier post).

Strong winds increase the volume of warm water that the Gulf Stream carries into the Arctic Ocean. They can also cause rain storms that can devastate Arctic ice and glaciers

Arctic sea ice currently has about the lowest extent for the time of the year since satellite measurements started in 1979.

The image below shows that, on February 17, 2015, Arctic sea ice had reached an extent of merely 14.406 million square kilometers.

click on image to enlarge
The Arctic sea-ice Monitor image below shows an extent of 13,774,725 km2 for February 18, 2015, with the red line illustrating the recent fall in extent even more dramatically.

Below is a 30-day animation showing sea ice thickness (in m) up to February 22, 2015 (and forecast up to March 2), from the U.S. Naval Research Laboratory.


As the Arctic's snow and ice cover decline, more sunlight gets absorbed that previously was reflected back into space. All this adds up to a very dangerous situation, since huge amounts of methane are contained in sediments under the seafloor of the Arctic Ocean, and they can get destabilized as the water warms up.

In conclusion, feedbacks make that the Arctic is warming more rapidly than the rest of the globe and they threaten to trigger huge methane eruptions from the seafloor of the Arctic Ocean.

Methane concentrations over the Arctic Ocean are very high at the moment. The image below shows the very high peak methane levels that have recently been recorded, against a background image showing high methane levels over the East Siberian Arctic Shelf on February 20, 2015.


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