Sunday, June 30, 2013
Cyclonic Activity persists in Arctic
Above image, edited from Naval Research Laboratory, shows that a large area has developed at the center of the Arctic Ocean with very thin ice, at some places down to virtually zero, i.e. open water.
This development is to a large extent caused by persistent cyclonic activity in the Arctic. The Arctic is warming up faster than anywhere else, and this is reducing the temperature difference between the Arctic and lower latitudes. As a result, the polar vortex and jet stream get distorted, resulting in extreme weather. This is graphically illustrated by the animation below, from the California Regional Weather Server.
Thursday, June 27, 2013
The Threat of Wildfires in the North
NASA/NOAA image based on Suomi NPP satellite data from April 2012 to April 2013, with grid added |
Vegetation in the Northern Band extends beyond the Arctic Circle (latitude 66° 33′ 44″ or 66.5622°, in blue on above image from Arcticsystem.no) into the Arctic, covering sparsely-populated areas such in Siberia, Alaska and the northern parts of Canada and Scandinavia. Further into the Arctic, there are huge areas with bush and shrubland that have taken thousands of years to develop, and once burnt, it can take a long time for vegetation to return, due to the short growing season and harsh conditions in the Arctic.
Above map with soil carbon content further shows that the top 100 cm of soil in the northern circumpolar region furthermore contains huge amounts of carbon.
May 16 2013 Drought 90 days Arctic |
June 25, 2013 from Wunderground.com - Moscow broke its more than 100-year-old record for the hottest June 27 |
On June 19, 2013, NASA captured this image of smoke from wildfires burning in western Alaska. The smoke was moving west over Norton Sound. (The center of the image is roughly 163° West and 62° North.) Red outlines indicate hot spots with unusually warm surface temperatures associated with fire. NASA image by Jeff Schmaltz, LANCE/EOSDIS Rapid Response. Caption by Adam Voiland. - also see this post with NASA satellite image of Alaska. |
Siberian wildfires June 21, from RobertScribbler |
from methanetracker.org |
|
Wildfires in the North threaten to cause large emissions of greenhouse gases and soot, which can settle on snow and ice in the Arctic and the Himalayan Plateau, with the resulting albedo changes causing a lot more sunlight to be absorbed, instead of reflected as was the case earlier. This in turn adds to the problem. Additionally, rising temperatures in the Arctic threaten to cause release of huge amounts of methane from sediments below the Arctic Ocean. This situation threatens to escalate into runway global warming in a matter of years, as illustrated by the image below.
How much will temperatures rise? |
The Climate Action Plan set out in above diagram can be initiated immediately in any country, without the need for an international agreement to be reached first. This can avoid delays associated with complicated negotiations and on-going verification of implementation and progress in other nations.
In nations with both federal and state governments, such as the United States of America, the Climate Action Plan could be implemented as follows:
- The President directs federal departments and agencies to reduce their emissions for each type of pollutant annually by a set percentage, say, CO2 and CH4 by 10%, and HFCs, N2O and soot by higher percentages.
- The President demands states to each make the same cuts.
- The President directs the federal Environmental Protection Agency (EPA) to monitor implementation of states and to act step in where a state looks set to fail to miss one or more targets, by imposing (federal) fees on applicable polluting products sold in the respective state, with revenues used for federal benefits.
This way, the decision how to reduce targets is largely delegated to state level, while states can similarly delegate decisions to local communities. While feebates, preferably implemented locally, are recommended as the most effective way to reach targets, each state and even each local community can largely decide how to implement things, provided that each of the targets are reached.
Similar targets could be adopted elsewhere in the world, and each nation could similarly delegate responsibilities to local communities. Additionally, it makes sense to agree internationally to impose extra fees on international commercial aviation, with revenues used to develop ways to cool the Arctic.
See also: Climate Plan |
Related
- Fires are raging again across Russia - June 22, 2012
http://arctic-news.blogspot.com/2012/06/fires-are-raging-again-across-russia.html
- Russia: 74 million acres burned through August 2012 - September 14, 2012
http://arctic-news.blogspot.com/2012/09/russia-74-million-acres-burned-through-august-2012.html
- How to avoid mass-scale death, destruction and extinction - December 31, 2012
http://arctic-news.blogspot.com/2012/12/how-to-avoid-mass-scale-death-destruction-and-extinction.html
- Turning forest waste into biochar - January 2, 2013
http://arctic-news.blogspot.com/2013/01/turning-forest-waste-into-biochar.html
- Climate Plan
Saturday, June 22, 2013
Open Water In Areas Around North Pole
In some areas around the North Pole, thickness of the sea ice has declined to virtually zero, i.e. open water.
What could have caused this open water? Let's go through some of the background.
North Hemisphere snow cover has been low for some time. Snow cover in May 2013 was the lowest on record for Eurasia. There now is very little snow left, as shown on the image right, adapted from the National Ice Center.
Low snow cover is causing more sunlight to be absorbed, rather than reflected back into space. As can be expected, there now are high surface temperatures in many areas, as illustrated by the NOAA image below. Anomalies can be very high in specific cases. Zyryanka, Siberia, recently recorded a high of 37.4 C, against normal high temperatures of 20 C to 21 C for this time of year. Heat wave conditions were also recorded in Alaska recently (satellite image of Alaska below).
Accordingly, a large amount of relatively warm water from rivers has flowed into the Arctic Ocean, in addition to warm water from the Atlantic and Pacific Oceans.
Sea surface temperatures have been anomalously high in many places around the edges of the sea ice, as also shown on the NOAA image below.
Nonetheless, as the above images also make clear, sea surface temperatures closer to the North Pole have until now remained at or below zero degrees Celsius, with sea ice cover appearing to remain in place. The webcam below from the North Pole Environmental Observatory shows that there still is a lot of ice, at least in some parts around the North Pole.
So, what could have caused the sea ice to experience such a dramatic thickness decline in some areas close to the North Pole?
Firstly, as discussed in earlier posts, there has been strong cyclonic activity over the Arctic Ocean (see also Arctic Sea Ice blog post). This has made the sea ice more prone and vulnerable to the rapid decline that is now taking place in many areas.
Furthermore, Arctic sea ice thickness is very low, as illustrated by the image below.
Finally, there has been a lot of sunshine at the North Pole. At this time of year, insolation in the Arctic is at its highest. Solstice (June 20 or June 21, 2013, depending on time zone) is the day when the Arctic receives the most hours of sunlight, as Earth reaches its maximum axial tilt toward the sun of 23° 26'. In fact, insolation during the months June and July is higher in the Arctic than anywhere else on Earth, as shown on the image below.
In conclusion, the current rapid sea ice thickness decline close to the North Pole is mostly due to a combination of earlier cyclonic activity and lots of sunlight, while the sea ice was already very thin to start with. The cyclone broke up the sea ice at the center of the Arctic Ocean, which is turn made it more prone to melting rapidly. The cyclone did more, though, as contributor to the Arctic-news blog Veli Albert Kallio explains:
The compilation of images below shows how the decline of sea ice has taken place in a matter of weeks.
This spells bad news for the future. It confirms earlier analyses (see links below) that the sea ice will disappear altogether within years. It shows that the sea ice is capable of breaking up abruptly, not only at the outer edges, but also at the center of the Arctic Ocean. As the Arctic sea ice keeps declining in thickness, it does indeed look set to break up and disappear abruptly across most of the Arctic Ocean within a few years. Models that are based on sea ice merely shrinking slowly from the outer edges inward should reconsider their projections accordingly.
Related
- Getting the Picture
http://arctic-news.blogspot.com/2012/08/getting-the-picture.html
- Supplementary evidence by Prof. Peter Wadhams
http://arctic-news.blogspot.com/2012/04/supplementary-evidence-by-prof-peter.html
What could have caused this open water? Let's go through some of the background.
North Hemisphere snow cover has been low for some time. Snow cover in May 2013 was the lowest on record for Eurasia. There now is very little snow left, as shown on the image right, adapted from the National Ice Center.
Low snow cover is causing more sunlight to be absorbed, rather than reflected back into space. As can be expected, there now are high surface temperatures in many areas, as illustrated by the NOAA image below. Anomalies can be very high in specific cases. Zyryanka, Siberia, recently recorded a high of 37.4 C, against normal high temperatures of 20 C to 21 C for this time of year. Heat wave conditions were also recorded in Alaska recently (satellite image of Alaska below).
NASA image June 17, 2013, credit: NASA/Jeff Schmaltz, LANCE MODIS Rapid Response Team, NASA GSFC - from caption by Adam Voiland: "Talkeetna, a town about 100 miles north of Anchorage, saw temperatures reach 96°F (36°C) on June 17. Other towns in southern Alaska set all-time record highs, including Cordova, Valez, and Seward. The high temperatures also helped fuel wildfires and hastened the breakup of sea ice in the Chukchi Sea." |
Sea surface temperatures have been anomalously high in many places around the edges of the sea ice, as also shown on the NOAA image below.
Nonetheless, as the above images also make clear, sea surface temperatures closer to the North Pole have until now remained at or below zero degrees Celsius, with sea ice cover appearing to remain in place. The webcam below from the North Pole Environmental Observatory shows that there still is a lot of ice, at least in some parts around the North Pole.
Webcam #2 of the North Pole Environmental Observatory monitoring UPMC's Atmospheric Buoy, June 21, 2013 |
Firstly, as discussed in earlier posts, there has been strong cyclonic activity over the Arctic Ocean (see also Arctic Sea Ice blog post). This has made the sea ice more prone and vulnerable to the rapid decline that is now taking place in many areas.
Furthermore, Arctic sea ice thickness is very low, as illustrated by the image below.
Arctic sea ice volume/extent ratio, adapted by Sam Carana from an image by Neven (click to enlarge) |
Monthly insolation for selected latitudes - adapted from Pidwirny, M. (2006), in "Earth-Sun Relationships and Insolation", Fundamentals of Physical Geography, 2nd Edition. |
"The ocean surface freezes if the temperature falls below -2.5C. The reason for the negative melting point is the presence of 4-5% of sea salt. Only in the polar regions does the sea surface cool sufficiently for sea ice to form during winters.Indeed, vertical mixing of the water column was enhanced due to cyclonic activity, and this occurred especially in the parts of the Arctic Ocean that also are the deepest, as illustrated by the animation below.
The sea ice cover is currently thinning near the North Pole between 80-90 degrees north. This part of the ocean is very deep. It receives heat of the Gulf Stream from the south: as the warm water vapourises, its salt content to water increases. This densifies the Gulf Stream which then falls onto the sea floor where it dissipates its heat to the overlying water column. The deep basin of the Arctic Ocean is now getting sufficiently warmed for the thin sea ice cover to thin on top of it. The transportation of heat to the icy surface is combined with the winds that push cold surface water down while rising heat to surface."
Legend right: Ice thickness in m from Naval Research Laboratory Legend bottom: Sea depth (blue) and land height (brown/green) in m from NIBCAO Arctic map at NOAA |
[ click to enlarge ] |
Related
- Getting the Picture
http://arctic-news.blogspot.com/2012/08/getting-the-picture.html
- Supplementary evidence by Prof. Peter Wadhams
http://arctic-news.blogspot.com/2012/04/supplementary-evidence-by-prof-peter.html
Thursday, June 20, 2013
Extreme weather becomes the norm - what can you do?
. . a sky that has turned red due to greenhouse gases, while the land is flooded. The handful of people who survived are standing by helplessly on higher grounds, in despair and without hope, while one figure turns to me in panic and pain, uttering nothing but a silent scream . . . (comment by Sam Carana, March 8, 2012, on auction of the Scream, by Edvard Munch) |
Symptoms
Torrential rains in some regions are causing massive floods while in other locales record droughts are occurring with higher frequency and severity and areal extent around the globe. Global food production is being hit hard, leading to large price increases and political instability. Areas under drought are experiencing numerous massive forest fires of incredible ferocity.
Causes
The statistics of extreme weather events have changed for the worst due to changes in the location, speed, and waviness of the jet streams which guide weather patterns and separate cold and dry northern air from warm and moist southern air. The jet streams have changed since the equator to north-pole temperature difference has decreased due to the huge temperature rise in the Arctic.
The huge temperature rise in the Arctic is due to a collapse in the area of highly reflective snow and ice, which is caused by melting. The melting is from warming from the increase of greenhouse gases from fossil fuel burning. The Arctic sea ice and spring snow cover will vanish within a few years and the weather extremes will increase at least 10x.
What can you do?
Go talk to you politicians and friends about climate change and the need to slash fossil fuel emissions. Immediately. Cut and paste my comments above and post them on facebook, send them to newspapers, and educate yourself on the science behind all the above linkages. Leave my name on or take it off and plagiarize all you want, just get this knowledge out there...
Paul Beckwith, B.Eng, M.Sc. (Physics),
Ph.D. student (Climatology) and Part-time Professor,
University of Ottawa
originally posted as a comment under the CBCnews post:
Calgary braces for flooding, orders communities evacuated
Related
- The Tornado Connection to Climate Change
- President Obama, here's a climate plan!
- Diagram of Doom
- Polar jet stream appears hugely deformed
- Ten Dangers of Global Warming (originally posted March 8, 2007)
Tuesday, June 18, 2013
Mean Methane Levels reach 1800 ppb
On May 9, the daily mean concentration of carbon dioxide in the atmosphere of Mauna Loa, Hawaii, surpassed 400 parts per million (ppm) for the first time since measurements began in 1958. This is 120 ppm higher than pre-industrial peak levels. This unfortunate milestone was widely reported in the media.
There's another milestone that looks even more threatening than the above one. On the morning of June 16, 2013, methane levels reached an average mean of 1800 parts per billion (ppb). This is more than 1100 ppb higher than levels reached in pre-industrial times (see graph further below).
Vostok ice core analysis shows that temperatures and levels of carbon dioxide and methane have all moved within narrow bands while remaining in sync with each other over the past 400,000 years. Carbon dioxide moved within a band with lower and upper boundaries of respectively 200 and 280 ppm. Methane moved within lower and upper boundaries of respectively 400 and 800 ppb.
Temperatures moved within lower and upper boundaries of respectively -8 and 2 degrees Celsius.
From a historic perspective, greenhouse gas levels have risen abruptly to unprecedented levels. While already at a historic peak, humans have caused emissions of additional greenhouse gases. There's no doubt that such greenhouse gas levels will lead to huge rises in temperatures. The question is how long it will take for temperatures to catch up and rise.
Below is another way of looking at the hockey stick. And of course, further emissions could be added as well, such as nitrous oxide and soot.
Large releases of methane must have taken place numerous times in history, as evidenced by numerous pockmarks, as large as 11 km (6.8 mi) wide.
Editor's update: Methane levels go up and down with the seasons, and differ by altitude. As above post shows, mean levels reached 1800 ppb in May 2013 at 586 mb, according to MetOp-2 data. Note that IPCC AR5 gives levels of 1798 ppb in 2010 and 1803 ppb in 2011, as further discussed in later posts such as this one. Also, see historic data as supplied by NOAA below.
There's another milestone that looks even more threatening than the above one. On the morning of June 16, 2013, methane levels reached an average mean of 1800 parts per billion (ppb). This is more than 1100 ppb higher than levels reached in pre-industrial times (see graph further below).
NOAA image |
Temperatures moved within lower and upper boundaries of respectively -8 and 2 degrees Celsius.
From a historic perspective, greenhouse gas levels have risen abruptly to unprecedented levels. While already at a historic peak, humans have caused emissions of additional greenhouse gases. There's no doubt that such greenhouse gas levels will lead to huge rises in temperatures. The question is how long it will take for temperatures to catch up and rise.
Below is another way of looking at the hockey stick. And of course, further emissions could be added as well, such as nitrous oxide and soot.
Large releases of methane must have taken place numerous times in history, as evidenced by numerous pockmarks, as large as 11 km (6.8 mi) wide.
Importantly, large methane releases in the past did not result in runaway global warming for a number of reasons:
- methane release typically took place gradually over many years, each time allowing a large release of methane to be broken down naturally over the years before another one occurred.
- Where high levels of methane in the atmosphere persisted and caused a lot of heat to be trapped, this heat could still be coped with due to greater presence of ice acting as a buffer and consuming the heat before it could escalate into runaway temperature rises.
Wikipedia image |
Veli Albert Kallio comments:
The problem with ice cores is that if there is too sudden methane surge, then the climate warms very rapidly. This then results the glacier surfaces melting away and the ice core begins to loose regressively surface data if there is too much methane in the air.
Because of this, there has been previous occurrences of high methane, and these were instrumental to bring the ice ages ice sheets to end (Euan Nisbet's Royal Society paper). The key to this is to look at some key anomalies and devise the right experiments to test the hypothesis for methane eruptions as the period to ice ages.
Thus, the current methane melting and 1800 ppm rise is nothing new except that there are no huge Pleistocene glaciers to cool the Arctic Ocean if methane goes to overdrive this time. In fact methane may have been many times higher than that but all surface ice kept melting away and staying regressive until cold water and ice from destabilised ice sheets stopped the supply of methane (it decays fast if supply is cut and temperatures fall back rapidly when seas rose).
The Laurentide Ice Sheet alone was equivalent of 25 Greenland Ice Sheets and the Weischelian and other sheets on top of that. So, the glaciers do not act the same way as fireman to extinguish methane. Runaway global warming is now possibility if the Arctic loses its methane holding capability due to warming.
Further discussion is invited on the following points:
- The large carbon-12 emission anomalies in East Asian historical objects that are dateable by historical knowledge. Discussion about the explanations concocted and why methane emission from permafrost soils and sea beds must be the answer;
- the much overlooked fact that if there were ever very highly elevated concentrations of air in the Arctic, this would induce strong melting of glaciers which then lack those surface depositions where the air were most CH4 and CO2 laden. Even moderate levels of temperature rise damaged Larsen A, Larsen B, Petermann and Ellesmere glaciers. If huge runaway outgassing came out when Beringia flipped into soil warming, then methane came out really large amounts with CO2.
- Discussion of the experiments how to compensate for the possible lack of "time" in methane elevated periods in the ice cores by alternative experiments to obtain daily, weekly, monthly and yearly emission rates of CH4 and CO2 from the Last Glacial Maximum to the Holocene Thermal Maximum (as daily, weekly, monthly, and yearly sampling of air).
Editor's update: Methane levels go up and down with the seasons, and differ by altitude. As above post shows, mean levels reached 1800 ppb in May 2013 at 586 mb, according to MetOp-2 data. Note that IPCC AR5 gives levels of 1798 ppb in 2010 and 1803 ppb in 2011, as further discussed in later posts such as this one. Also, see historic data as supplied by NOAA below.
Post by Sam Carana.
Sunday, June 16, 2013
Arctic Sea Ice September 2013 Projections
What will the Arctic Sea Ice look like in September 2013?
Several projections for Arctic sea ice extent are being discussed at places such as ARCUS (Arctic Research Consortium of the United States) and the Arctic Sea Ice Blog. The image below, from ARCUS, shows various projections of September 2013 arctic sea extent (defined as the monthly average for September) with a median value of 4.1 million square kilometers, with quartiles of 3.8 and 4.4 million square kilometers.
Note that sea ice extent in the above projections is defined as area of ocean with at least 15% ice, in line with the way the NSIDC calculates extent. By contrast, the Danish Meteorological Institute includes areas with ice concentration higher than 30% to calculate ice extent.
Rather than looking at the projected average for September, one could also project the minimum value for September 2013. And rather than looking at sea ice extent, one could also look at sea ice area, which differs from sea ice extent as the NSIDC FAQ page describes:
Above image shows Sam Carana's projected minimum area of 2 million square km for 2013, based on data by Cryosphere Today and on numerous factors, such as continued warming of the water underneath the ice, stronger cyclones, etc.
Roughly in line with above image, by Wipneus, Sam Carana's projection for Arctic sea ice minimum volume is 2,000 cubic km in September 2013.
Readers are invited to submit comments below with further projections.
Several projections for Arctic sea ice extent are being discussed at places such as ARCUS (Arctic Research Consortium of the United States) and the Arctic Sea Ice Blog. The image below, from ARCUS, shows various projections of September 2013 arctic sea extent (defined as the monthly average for September) with a median value of 4.1 million square kilometers, with quartiles of 3.8 and 4.4 million square kilometers.
Note that sea ice extent in the above projections is defined as area of ocean with at least 15% ice, in line with the way the NSIDC calculates extent. By contrast, the Danish Meteorological Institute includes areas with ice concentration higher than 30% to calculate ice extent.
Rather than looking at the projected average for September, one could also project the minimum value for September 2013. And rather than looking at sea ice extent, one could also look at sea ice area, which differs from sea ice extent as the NSIDC FAQ page describes:
A simplified way to think of extent versus area is to imagine a slice of Swiss cheese. Extent would be a measure of the edges of the slice of cheese and all of the space inside it. Area would be the measure of where there is cheese only, not including the holes. That is why if you compare extent and area in the same time period, extent is always bigger.
Above image shows Sam Carana's projected minimum area of 2 million square km for 2013, based on data by Cryosphere Today and on numerous factors, such as continued warming of the water underneath the ice, stronger cyclones, etc.
Roughly in line with above image, by Wipneus, Sam Carana's projection for Arctic sea ice minimum volume is 2,000 cubic km in September 2013.
Readers are invited to submit comments below with further projections.
Thursday, June 13, 2013
Arctic sea ice thickness falls by 2m in 21 days in some areas
For years, warnings have been raised about the dramatic decline of Arctic sea ice. Various posts at this blog have also analyzed the exponential nature of the decline in summer sea ice volume and the many feedbacks that fuel this decline. And for years, the conclusion has been that - without action - the sea ice looks set to disappear altogether within years.
Yet, many are still ignoring this warning, often with remarks such as "some of the ice is 5 meters thick; it would take decades for all that ice to melt!" Thick ice does indeed pile up along the northern coast of Greenland and Ellesmere Island, due to the way the ice drifts. This has lead some to argue that an S-shaped curve (sigmoid or gompertz trendline) was more appropriate, with the decline in sea ice volume slowing down as it approaches zero.
However, this argument doesn't seem make much sense, since such a S-shaped trendline would only apply to a relatively small area with very thick sea ice. Exponential curves would still remain the best fit to predict the decline of the sea ice in the Arctic Ocean at large.
Moreover, is it really more appropriate to say that summer sea ice looks set to virtually disappear within years, with just a tiny sliver of ice remaining north of Greenland and Ellesmere Island, instead of saying that the sea ice looks set to disappear altogether within years? How persistent will such a sliver really be?
One of the feedbacks of sea ice decline is that, as the decline progresses, cyclones can be expected to hit the remaining sea ice ever harder. How much damage can such cyclones and further feedbacks do? A previous post describes thin spots developing in the sea ice under the influence of a cyclone. The image below shows areas at the center of the Arctic Ocean (large circle) where thickness of the sea ice fell from 2 meters to 1 meters over a period of 21 days. Furthermore, the image below also shows that, over this period, 5m-thick ice was reduced to 3-meters thickness (top small circle), while 2m-thick ice was reduced to zero (bottom small circle).
In conclusion, without action the Arctic sea ice looks set to continue to decline exponentially, while strong feedbacks such as cyclones developing when there is more open water, look set to add to the decline and cause the Arctic sea ice to disappear completely within years. For an overview of lines of action, see this post at the methane hydrates blog.
Yet, many are still ignoring this warning, often with remarks such as "some of the ice is 5 meters thick; it would take decades for all that ice to melt!" Thick ice does indeed pile up along the northern coast of Greenland and Ellesmere Island, due to the way the ice drifts. This has lead some to argue that an S-shaped curve (sigmoid or gompertz trendline) was more appropriate, with the decline in sea ice volume slowing down as it approaches zero.
However, this argument doesn't seem make much sense, since such a S-shaped trendline would only apply to a relatively small area with very thick sea ice. Exponential curves would still remain the best fit to predict the decline of the sea ice in the Arctic Ocean at large.
Moreover, is it really more appropriate to say that summer sea ice looks set to virtually disappear within years, with just a tiny sliver of ice remaining north of Greenland and Ellesmere Island, instead of saying that the sea ice looks set to disappear altogether within years? How persistent will such a sliver really be?
One of the feedbacks of sea ice decline is that, as the decline progresses, cyclones can be expected to hit the remaining sea ice ever harder. How much damage can such cyclones and further feedbacks do? A previous post describes thin spots developing in the sea ice under the influence of a cyclone. The image below shows areas at the center of the Arctic Ocean (large circle) where thickness of the sea ice fell from 2 meters to 1 meters over a period of 21 days. Furthermore, the image below also shows that, over this period, 5m-thick ice was reduced to 3-meters thickness (top small circle), while 2m-thick ice was reduced to zero (bottom small circle).
2m falls in thickness in 21 days - click on image to enlarge |
Thursday, June 6, 2013
Thin Spots developing in Arctic Sea Ice
From the start of 2013, Arctic sea ice extent has roughly followed the same path it did in 2012 when a historic record low was reached, as discussed in a previous post. At the moment, thinner spots are developing in the sea ice, as illustrated by the image below.
These thin spots are developing due to a combination of factors:
These thin spots are developing due to a combination of factors:
- a cyclone over the Arctic
- low North Hemisphere snow cover causing more sunlight to be absorbed, rather than reflected back into space
- warm sea surface temperatures at edges of sea ice, as illustrated by the image below
- ice thickness is very low, as illustrated by the image further below
NOAA image, click to enlarge |
Arctic sea ice volume/extent ratio by Neven (click to enlarge image) |
Below, a 30-day Naval Research Laboratory animation illustrating the development of the thinner spots.
Tuesday, June 4, 2013
The Tornado Connection to Climate Change
By Paul Beckwith, B.Eng, M.Sc. (Physics),
Ph.D. student (Climatology) and Part-time Professor,
University of Ottawa
|
"In 2012, 93 percent of natural catastrophes were weather-related disasters. The United States was seriously affected: it accounted for 69% of overall losses and 92% of insured losses due to natural catastrophes worldwide." ~ World Watch Institute
"America has some of the wildest weather on the planet, and it turns out those extremes – which run from heat waves and tornadoes to floods, hurricanes and droughts – carry a heavy price tag." ~ theguardian
3D look at the Moore Oklahoma thunderstorm and tornado, up to 50,000 ft. Image by Tony Petrarca from Tony's Pinpoint Weather Blog showing the funnel touching the ground just outside of Moore. |
The actual tornado tracked through the most built up part of the city and had a length of 6.22 km (Image 2). As bad as this was, if the tornado had tracked further north by about 10 km, the path length through the built-up part of the city would have been about 28 km and likely would have resulted in FOUR TIMES MORE DAMAGE.
The high altitude jet stream guided this storm directly over Oklahoma City and was a key ingredient responsible for the extremely rapid development of the tornado witnessed. Unfortunately, the location, strength, waviness, and behavior of the jet stream is changing as a result of rapid climate change. You can get use to more “Climate Bomb” extreme weather events – there is nothing to be surprised about here.
Greenhouse gas emissions from humans have warmed the planet since about 1850; the warming rate has stepped up a notch over the past several decades, and even more so now with ‘feedbacks’ kicking in big time.
There is less snow cover on the land over northern Canada, northern Eurasia and Siberia, and there is less sea ice over the Arctic Ocean. The snow and ice reflects greater than 80% of the incoming light from the sun back into space keeping these areas colder. With less snow the dark land is uncovered and with less sea ice the dark ocean is uncovered. These both reflect much less light; only about 20% and 10% respectively. The rest is absorbed and heats the ground and sea. The melting ground is releasing methane; the warming sea heats the sea floor and that warming releases more methane. Thus, parts of the high Arctic are warming at 5 to 6 times the average global rate. The equator temperature does not change as much (even seasonally the change is only about 3°C over the year). Thus, the temperature gradient between the equator and Arctic is greatly reduced.
By basic physics and meteorology, this reduced equator-pole temperature difference slows the west to east wind component. Fast jet streams circle the earth from west to east; as they slow they become much wavier and travel much more northward and southward. Regions north of the wavy jets are cold and dry (air source is cold Arctic) while regions south of the wavy jets are hot and moist (air source is equatorial marine regions). The jet is thus an intersection of these two different types of air masses (with cold fronts and warm fronts, respectively). The large local temperature gradients give rise to large pressure gradients resulting in extreme (and very unstable) weather regions.
May 20, 2013 Moore, Oklahoma tornado |
Global warming also brings greater ocean evaporation and warmer air can carry more water vapor – in fact, in the last 3 decades or so there has been a 4% increase in atmospheric humidity. When this water vapor condenses to forms clouds, energy is released. Greater energy in the atmosphere thus fuels more violent storms, and Climate Bombs are born.
The Oklahoma tornado is just another example of the global ‘weirding‘ that we are seeing. Our reference frame is the “old climate”, in which the equator-polar temperature gradients are smaller, but the local frontal temperature gradients are larger. In our “new climate” (in which there is much less sea ice in the Arctic) this type of tornado will be much more probable — at least while we abruptly transition from the “old” to the “new” and unfamiliar climate.
Our future is a world with much warmer global temperatures. Paleoclimate records show temperature rises of 6 to 10°C within two decades have occurred many times in the past over Greenland; in one case the rise was 16°C. I see no reason why this will not occur again.
Put your seat belt on . . . oil profits can’t save you from Climate 2.0.
Related posts
[earlier published at Paul's blog at SierraClubCanada and BoomerWarrior]
Related posts
- Killer El Reno Tornado Was Widest Ever Recorded: NWS
- Climate change causing US wildfire season to last longer, Congress told
Update on Arctic Snow and Ice
Above image, adapted from the National Snow and Ice Data Center (NSIDC), shows that Arctic sea ice extent has roughly followed the same path it did in 2012 when it reached a historic record low. Highlighted on above image is the highest extent the sea ice reached in 2013, i.e. 15,113 million square km on May 14, 2013.
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