Showing posts with label current. Show all posts
Showing posts with label current. Show all posts

Wednesday, February 19, 2020

Arctic Ocean February 2020


On February 20, 2020, 09Z, surface temperature anomalies reached both ends of the scale over North America, while the Arctic was 3.7°C or 6.7°F warmer than in 1979-2000. On that day, the average 2 m temperature anomaly for the Arctic was 3.5°C or 6.3°F.


These high temperature anomalies at 2 meters in the left panel go hand in hand with the wind patterns at 250 hPa (jet stream) as shown in the center panel and the wind patterns at 10 meters shown in the right panel. Closer to sea level, circular winds around low pressure areas bring warm air into the Arctic, from Russia and from the Pacific Ocean.


Above image shows winds at 250 hPa (jet stream) with speeds as high as 317 km/h or 197 mph (green circle) in the left panel, while the right panel shows circular winds at 850 hPa reaching speeds as high as 176 km/h or 109 mph (green circle).

These wind patterns have caused much warm air to enter the Arctic, while relatively little cold air has moved out of the Arctic. Furthermore, stronger winds cool the sea surface. As a result, Arctic sea ice extent on February 24, 2020, was 14.1 million km², slightly more than the 2010s average of 14 million km².


Arctic sea ice, however, is very thin. Stronger winds can also accelerate the speed at which ever warmer water is flowing into the Arctic Ocean from the Atlantic Ocean and from the Pacific Ocean, as discussed in a previous post. The overall result is that sea ice volume is at a record low for the time of the year.


This is further illustrated by the sea ice thickness (in meters) comparison below between February 28, 2015 and February 28, 2020, i.e. forecasts for February 28, run on February 27.



Rise in greenhouse gas levels is accelerating

Temperatures are rising at ever faster speed as the rise in greenhouse gas levels in the atmosphere is accelerating. As illustrated by the image below, the daily average CO₂ level at Mauna Loa, Hawaii, was 416.08 ppm on February 10, 2020, higher than it has been for millions of years. Since the annual peak is typically reached in May, even higher levels can be expected soon.


From the way emissions are rising now, it looks like we could soon reach even higher CO₂e forcing than during the Paleocene–Eocene Thermal Maximum (PETM) mass extinction event, some 55.5 million years ago, as discussed in a previous post. Very worrying also is the recent rise in methane levels recorded at Barrow, Alaska, as illustrated by the image below.


The buffer is gone

As the sea ice is getting thinner, there is little or no buffer left to consume the influx of ever warmer and salty water from the Atlantic Ocean and Pacific Ocean. As illustrated by the image below, there is a tipping point at 1°C above the 20th century average, i.e. there are indications that a rise of 1°C will result in most of the sea ice underneath the surface to disappear.

[ from earlier post ]
As long as there is sea ice in the water, this sea ice will keep absorbing heat as it melts, so the temperature will not rise at the sea surface. But there is ever less sea ice volume left to absorb ocean heat, and the amount of energy absorbed by melting ice is as much as it takes to heat an equivalent mass of water from zero to 80°C.


Meanwhile, temperatures keep rising globally and more than 90% of global warming is going into oceans.


As the temperature of the oceans keeps rising, the danger increases that heat will reach the seafloor of the Arctic Ocean and will destabilize hydrates contained in sediments at the seafloor, resulting in huge releases of methane.


Are humans functionally extinct?

For more background as to when temperatures
could cross 2°C, see also this discussion on trends 
Species can be regarded to be ‘functionally extinct’ when their numbers have declined below levels needed for them to reproduce healthy offspring. This can occur due to causes such as loss of habitat and disappearance of other species that they depend on.

Species can also be declared to be ‘functionally extinct’ when they are threatened to be wiped out by a catastrophe that appears to be both imminent and inescapable, which would cause their numbers to dwindle below a critical threshold required for survival of the species.

Rising temperatures now threaten most, if not all, species to go extinct in a matter of years. In 2020, the global temperature rise could cross the critical guardrail of 2°C above preindustrial that politicians at the Paris Agreement promised would not be crossed. In fact, they pledged to take efforts to avoid a 1.5°C rise. Their failure to do so constitutes a de facto declaration that humans are now functionally extinct and that the looming temperature rise will drive most, if not all species on Earth into extinction.

See also the 2015 postWARNING - 
Dire Situation

The situation is dire, in many respects. Current laws punish people for the most trivial things, while leaving the largest crime one can imagine unpunished: planetary omnicide!

In the video below, Guy McPherson warns that a rapid decline in industrial activity could result in an abrupt rise in temperature of 1°C, as much of the aerosol masking effect falls away.


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

P.S. Don't forget to vote!

One of the most important things one can do to change things is to vote, e.g. in the U.S., vote for Bernie Sanders and the Green New Deal!

Fossil fuel and control over its supply is behind much of the conflict, violence and pollution that has infested the world for more than a century.

Instead of using fossil fuel, the world must rapidly transition to the use of wind turbines, geothermal power, solar power, wave power, and similar clean and renewable ways to generate energy.

The transition to clean, renewable energy removes much cause for conflict, since it is available locally around the world and its use in one place doesn't exclude use of clean, renewable energy elsewhere.

The transition to clean, renewable energy will provide greater energy security and reliability, besides its numerous further benefits, e.g. it will make more land and water available for growing food and it will give us more jobs, better health, and a cleaner environment. And, because it's more economic, the transition to clean, renewable energy will pay for itself as we go.

Bernie Sanders calls for a rapid transition to clean, renewable energy as part of the Green New Deal.

Please share this message, vote for Bernie Sanders and support the GND!




Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• Why stronger winds over the North Atlantic are so dangerous
https://arctic-news.blogspot.com/2020/02/why-stronger-winds-over-north-atlantic-are-so-dangerous.html

• Critical Tipping Point Crossed In July 2019
https://arctic-news.blogspot.com/2019/09/critical-tipping-point-crossed-in-july-2019.html

• Could Humans Go Extinct Within Years?
https://arctic-news.blogspot.com/2020/01/could-humans-go-extinct-within-years.html

• January 2020 Temperature Anomaly
https://arctic-news.blogspot.com/2020/02/january-2020-temperature-anomaly.html


Saturday, September 6, 2014

Antarctica linked to Arctic

Waters in the Arctic Ocean continue to warm up. Very warm waters from the North Atlantic and Pacific Ocean are invading the Arctic Ocean.



Waters in the North Atlantic and in the North Pacific are very warm, due to a number of reasons.

What is happening in the oceans is very important in this respect. As discussed in earlier posts, most of the extra heat caused by people's emissions goes into the oceans.

The great ocean conveyor belt (Thermohaline Circulation), brings warm water from the southern hemisphere to the northern hemisphere.

The Gulf Stream is the North Atlantic leg of the great ocean conveyor belt, and it brings dense, salty water from the North Atlantic into the Arctic Ocean.

Saltier water is denser than fresher water because the dissolved salts fill interstices between water molecules, resulting in more mass per unit volume.

Very dense ocean water can be found in the North Atlantic because the North Atlantic has high salinity, due to high evaporation rates, while salty water is also coming from the Mediterranean Sea.

As also discussed in an earlier post, this dense, saltier water sinks in the North Atlantic, accumulating in deeper water.

By contrast, much of the Arctic Ocean has low salinity, due to ice melt and river runoff.  As it enters the Arctic Ocean, the warm and dense water from the Atlantic thus dives under the under the sea ice and under the less salty surface water in the Arctic Ocean.

In conclusion, much of the heat resulting from people's emissions accumulates in the North Atlantic and also ends up in the Arctic. This partly explains why surface temperatures are rising much faster at the poles, as illustrated by the NOAA image below.


There are further reasons why surface air temperatures elsewhere (other than at the poles) are rising less rapidly than they did, say, a decade ago. As also discussed by Andrew Glikson in the post No Planet B, the increased amounts of sulphur emitted by the growing number of coal-fired power plants and by the burning of bunker fuel on sea is (temporarily) masking the full wrath of global warming.

Another reason is the growth of the sea ice around Antarctica, as illustrated by the CryosphereToday image on the left.

Melting takes place both in the Arctic and on Antarctica, but more so in the Arctic. Recent research of CryoSat-2 data reveals that Greenland alone is now losing about 375 cubic kilometers of ice annually, while in Antarctica the annual volume loss now is about 125 cubic kilometers.

Currents also distribute ocean heat in ways that make the Arctic warm up more than twice as rapidly as the Antarctic. In a recent paper, John Marshall et al. further suggest that ozone depletion also contributes to this.

All this makes that, while the jet streams on the northern hemisphere are circumnavigating the globe at a slower pace, jet streams on the southern hemisphere are getting stronger, making it more difficult for warm air to enter the atmosphere over Antarctica, while the stronger winds also speed up sea currents on the southern hemisphere. This makes the sea ice around Antarctica grow, and as the sea ice spreads further away from Antarctica, temperatures of surface waters around Antarctica are falling.

Growth of the sea ice around Antarctica makes that more sunlight is reflected back into space. There now is some 1.5 million square kilometers more sea ice around Antarctica than there used to be. The albedo change associated with sea ice growth on the southern hemisphere can be estimated at 1.7 W/sq m, i.e. more than the total RF of all CO2 emission caused by people from 1750 to 2011 (IPCC AR5).


The rapid growth of sea ice on the southern hemisphere alone goes a long way to explain why, over the past three months, surface air temperatures have not been much higher than they used to be, both globally and in the Arctic, as illustrated by above NOAA image. What has also contributed to warmer temperatures around latitude 60 on the northern hemisphere is the fact that methane has accumulated in the atmosphere at that latitude, as discussed in earlier posts.

Arctic SST far exceed anything ever seen in human history
So, does the sea ice on the southern hemisphere constitute a negative feedback that could hold back global warming? It doesn't.

It may temporarily keep surface temperatures close to what they used to be, as the sea ice reflects lots of sunlight back into space, but at the same time ocean temperatures are rising strongly, as the sea ice also prevents heat from radiating out of the waters around Antarctica.

The latter also helps explaining the colder surface temperatures over those waters.

Much of this additional ocean heat has meanwhile been transported by the great ocean conveyor belt to the northern hemisphere.

No time before in human history has such a huge amount of ocean heat accumulated in the North Atlantic and the North Pacific. This heat is now threatening to invade the Arctic Ocean and trigger huge temperature rises due to methane eruptions from the seafloor.


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

Wednesday, January 8, 2014

High Methane Levels over Arctic Ocean continue in 2014

The high methane levels over the Arctic Ocean, the biggest story of 2013, continue in 2014, as illustrated by the image below.


As above image shows, high methane readings (as high as 2301 ppb on January 6, 2014) continue in 2014. High methane concentrations continue to enter the atmosphere where the sea ice is thin and where the sea ice is carried by currents outside of the Arctic Ocean.

The inset shows ice thickness on January 6, 2014. The inset highlights the huge amounts of sea ice that are carried by the sea current from the north of Greenland into the Atlantic Ocean.

What is the impact of these high methane releases over the Arctic Ocean on global methane levels? The image below shows the most recent global methane levels available from NOAA.


The image below shows readings from surface flask at Mauno Loa, Hawaii, with two recent readings (in the top right corner) reaching levels close to 1880 ppb.


Clearly, methane levels are rising globally and high releases over the Arctic Ocean are contributing to the global rise. The images below show recent data from stations in the Arctic, i.e. the image below showing readings from in situ measurements at the station at Barrow, Alaska, and the image further below showing flask samples taken at Tiksi, Russia.



Note that the above images reflect land-based measurements taken at altitudes that are typically too low to capture the extent at which methane is rising in the atmosphere over the Arctic Ocean. Nonetheless, the wind can at times carry along some of the methane from the Arctic Ocean, as is apparent in a number of readings in above images showing levels of over 2100 ppb.

The image below shows high methane releases over the Arctic Ocean, as recorded on (part of) January 7, 2014, when levels were reached as high as 2381 ppb.


The image below shows methane levels on (part of) January 8, 2014, when levels as high as 2341 ppb were recorded. The inset confirms indications that these high levels originate from the Arctic Ocean.


These high methane concentrations over the Arctic are contributing to high temperature anomalies that further accelerate warming in the Arctic, as illustrated by the image below.


For a more detailed description of the kinds of warming and feedbacks that are hitting the Arctic, see the post The Biggest Story of 2013.



Thursday, December 26, 2013

Sea Ice in decline between Svalbard and Greenland

[ click on image to enlarge ]
Above image shows that Earth's highest atmospheric methane concentrations are recorded over the Arctic Ocean. The insets show lower methane concentrations over various continents, North and South America (top left), Europe (mid right), Australia bottom left) and Antarctica (bottom right).

The top right inset shows sea ice thickness, illustrating that methane is escaping from the sea floor of the Arctic Ocean and is transported by currents to the thinner edges of the sea ice, where it is entering the atmosphere.

As discussed in a recent post, methane can be bubbling up in the Arctic Ocean with a force strong enough to prevent sea ice from forming in the area. This feedback is depicted in the Diagram of Doom further below as feedback #13.


Around this time of year, Arctic sea ice is typically growing rapidly, both in extent and thickness.

However, the above image shows that in the area marked by the white circle, between Svalbard and Greenland, the sea ice is actually in decline.

[ click on image to enlarge ]
This decline is caused by methane that is entering the atmosphere in the area as warmer water continues to be transported by the Gulf Stream into the Arctic Ocean, as discussed in previous posts such as this one, and as also illustrated by the image on the right.

Warmer than average waters have been entering the Arctic Ocean along the Gulf Stream since July 2013, when changes to the Jet Stream contributed to waters off the North American coast reaching record warmest temperatures, as depicted in the Diagram of Doom below as feedback #11.

In summary, the above images show that methane makes it hard for ice to form, while the warm water of the West Spitzbergen Current is pushing the ice away, breaking up even the thickest ice to the north of Greenland.

Surface temperatures in the area have been extremely high recently. This part of the Arctic Ocean was hit by an 18+°C anomaly during the week from December 16 to December 22, 2013, as illustrated by the image below.


On some days that week, anomalies of 20+°C were recorded over an even larger part of the Arctic Ocean, as described in a previous post. These anomalies show how a number of feedbacks can interact and contribute to huge warming peaks in the Arctic Ocean, such as methane releases (feedbacks #2 and #13 in the diagram below) and changes to the Jet Stream (feedbacks #10 and #11 in the diagram below).

This spells bad news for the sea ice. Some people may have hoped that the thicker sea ice north of Greenland would take decades to disappear. However, as depicted in the Diagram of Doom below, feedbacks can hugely accelerate sea ice decline. As sea ice declines further, more open water make it more likely that stronger storms and cyclones will appear that can rip the sea ice apart and move the pieces into the Atlantic Ocean in a matter of days.

The image below, by Jim Pettit, illustrates the ongoing decline of the sea ice.


Thirteen feedbacks that can accelerate warming in the Arctic are depicted in the diagram below.


Specific feedbacks are described in the following posts:
- Diagram of Doom
- Further feedbacks of sea ice decline in the Arctic
- Causes of high methane levels over Arctic Ocean
- Methane Release caused by Earthquakes
- How Do We Act in the Face of Climate Chaos?
- The astounding global warming impact on our oceans . . .
- Methane emerges from warmer areas
Feedbacks are pictured in a more general way in the image below.


Above image shows how the accumulation of the many feedbacks and their interaction leads to ever stronger albedo changes, while the resulting accelerated warming in the Arctic causes increasing quantities of methane to be released from the seafloor of the Arctic Ocean, in turn leading to runaway global warming, as also pictured in the image below.

[ click on image to enlarge ]
As above image shows, a polynomial trendline already points at global temperature anomalies of 5°C by 2060. Even worse, a polynomial trendline for the Arctic shows temperature anomalies of 4°C by 2020, 7°C by 2030 and 11°C by 2040, 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 20°C+ by 2050.

To reduce these risks, comprehensive and effective action is needed, such as described at the Climate Plan blog.

Thursday, October 31, 2013

Causes of high methane levels over Arctic Ocean

Methane levels in the atmosphere over the Arctic Ocean are very high, as illustrated by the image below, by Leonid Yurganov, showing IASI methane readings for October 11-20, 2013.


Previous posts have discussed these high levels of methane, pointing at links between high methane levels over Arctic Ocean and earthquakes and volcanic activity.

Malcolm Light points at another factor that is contributing to the high methane levels observed over the Arctic Ocean in October 2013.

Malcolm says: The massive methane release in the Arctic this October is partly because the Gulf Stream waters got massive heating in the Atlantic off the North American coast in July. It takes the Gulf Stream currents almost 4 months to reach the emission sites along the southern side and end of the Eurasian Basin. This combined with the earthquake activity along the Gakkel Ridge and deep pyroclastic eruptions is escalating the rate of methane release by destabilizing the submarine Arctic methane hydrates at increasing rates.

The NOAA image below shows temperature anomalies for July 2013. NOAA adds that in July 2013 many regions were much warmer than average, with part of the northeastern Atlantic off the coast of North America observing record warmth.


The image below shows how water traveling along the Gulf Stream ends up in the Arctic Ocean. Water in the Gulf Stream travels at 4 miles per hour, but slows down to less than 1 mile per hour in the North-Atlantic Current. This means that water warmed up off Florida in July will start reaching waters beyond Svalbard in October.


The image below, from Malcolm Light's September 2012 post Further Confirmation of a Probable Arctic Sea Ice Loss by Late 2015, shows how warm water flows into the Arctic Ocean and warms up methane hydrates and free gas held in sediments under the Arctic Ocean.
 The image below shows the methane readings over the past few days on the Northern Hemisphere.


Tuesday, August 28, 2012

Diagram of Doom



Above diagram was part of a poster displayed at the 2011 AGU meeting in San Francisco by the Arctic Methane Emergency Group (AMEG). It was accompanied by the following text: In the Arctic, three problems are compounding one another: emissions causing global warming, sea ice loss causing accelerated warming, and methane releases further accelerating Arctic warming, with the danger of triggering runaway global warming.

The diagram pictures three kinds of warming and their main causes:
  1. Emissions by people causing global warming, with temperatures rising around the globe, including the Arctic.
  2. Soot, dust and volatile organic compounds settling down on snow and ice, causing albedo change. More heat is absorbed, rather than reflected as was previously the case. This causes accelerated warming in the Arctic.
  3. Accelerated warming in the Arctic threatening to weaken methane stores in the Arctic with the danger that methane releases will trigger runaway global warming.

The diagram also pictures two feedback effects that make things even worse:
  • Albedo feedback: Accelerated warming in the Arctic speeds up sea ice loss, further accelerating albedo change.
  • Methane feedback: Methane releases in the Arctic further add to the acceleration of warming in the Arctic, further contributing to weaken Arctic methane stores and increasing the danger that methane releases will trigger runaway global warming.

Albedo change in the Arctic comprises a number of elements, as depicted in the image below, from the 2004 report Impacts of a Warming Arctic - Arctic Climate Impact Assessmentby the International Arctic Science Committee.  


As described in various posts at this blog over time, there are further points that should be taken into account. Regarding sea ice loss, it's clear that where sea ice retreats, more open water appears, with the result that less sunlight is reflected back into space. Accelerated warming will also affect the integrity of the remaining sea ice, as well as of the snow and ice cover on land, including glaciers. This further adds to the albedo effect, causing less sunlight to be reflected back into space. Similarly, further feedbacks could be added or described in more detail.

Accordingly, ten feedbacks can be identified, and described as follows:
  1. Albedo feedback: Accelerated warming in the Arctic speeds up the decline of ice and snow cover, further accelerating albedo change. 
  2. Methane feedback: Methane releases in the Arctic further add to the acceleration of warming in the Arctic, further contributing to weaken Arctic methane stores and increasing the danger that methane releases will trigger runaway global warming. 
  3. Currents feedback: Sea ice loss can cause vertical sea currents to weaken, reducing the cooling effect they had on the seabed. This can thus further cause sediments to warm up that can contain huge amounts of methane in the form of free gas and hydrates. 
  4. Storms feedback: Increased frequency and intensity of storms can cause substantially more vertical mixing of the sea water column, causing more warming of the seabed, thus further contributing to the warming of sediments, as above. 
  5. Storms feedback: Accelerated warming in the Arctic can result in more storms, causing mixing of cold Arctic air with warmer air from outside the Arctic. The net result is a warmer Arctic. 
  6. Storms feedback: More open waters can result in more storms that can push the ice across the Arctic Ocean, and possibly all the way out of the Arctic Ocean. 
  7. Storms feedback: Storms also cause more waves that break up the sea ice. Smaller pieces of ice melt quicker than large pieces. A large flat and solid layer of ice is also less susceptible to wind than many lighter and smaller pieces of ice that will stand out above the water and capture the wind like the sails of yachts. 
  8. Storms feedback: Storms cause waters to become more wavy. Calm waters can reflect much sunlight back into space, acting as a mirror, especially when the sun shines under a low angle. Wavy waters, on the other hand, absorb more sunlight. 
  9. Fires feedback: More extreme weather comes with heatwaves and storms. Thus, this is in part another storms feedback. The combination of storms and fires can be deadly. Heatwaves can spark fires that, when fueled up by storms, turn into firestorms affecting huge areas and causing huge amounts of emissions. Storms can whip up particles that when deposited on ice, snow or the bare soil, can cause more sunlight to be absorbed. 
  10. Open doors feedback: Accelerated warming in the Arctic causes the polar vortex and jet stream to weaken, causing more extreme weather and making it easier for warm air to enter the Arctic.

These ten feedback are depicted in the diagram below.