Showing posts with label water vapor. Show all posts
Showing posts with label water vapor. Show all posts

Sunday, January 20, 2019

Care for the Ozone Layer


The stratosphere normally is cold and very dry. Global warming can increase water vapor in the stratosphere in a number of ways. Global warming causes the troposphere to warm and since warmer air holds more water vapor, the amount of water vapor in the troposphere is increasing. This can cause more water vapor to end up in the stratosphere as well, as described below.

Stratospheric Water Vapor over the Arctic

Around the time of the December Solstice, very little sunlight is reaching the Arctic and temperatures over land at higher latitudes can get very low. At the same time, global warming has made oceans warmer and this keeps air temperatures over water relatively warm in Winter. This can lead to a number of phenomena including sudden stratospheric warming and moistening of the stratosphere.

Sudden stratospheric warming is illustrated by the image on the right, showing temperatures in the stratosphere over Siberia as high as 12.7°C or 54.9°F on December 24, 2018, and temperatures as low as -84.8°C or -120.6°F over Greenland.

At the same time, relative humidity was as high as 100% in the stratosphere over the North Sea, as the second image on the right shows.

Moistening of the stratosphere was even more pronounced on December 24, 2016, as illustrated by the third image on the right.

Storms over the U.S.

Jennifer Francis has long pointed out that, as temperatures at the North Pole are rising faster than at the Equator, the Jet Stream is becoming wavier and can get stuck in a 'blocking pattern' for days, increasing the duration and intensity of extreme weather events.

This can result in stronger storms moving more water vapor inland over the U.S., and such storms can cause large amounts of water vapor to rise high up in the sky.

Water vapor reaching stratospheric altitudes causes loss of ozone, as James Anderson describes in a 2017 paper and discusses in the short 2016 video below.


Methane

Stratospheric water vapor can also result from methane oxidation in the stratosphere. Methane concentrations have risen strongly at higher altitudes over the years. Noctilucent clouds indicate that methane has led to water vapor in the upper atmosphere.

The danger is that, as the Arctic Ocean keeps warming, large eruptions of methane will occur from the seafloor. Ominously, high methane levels have recently shown up on satellite images over the Arctic at lower altitudes, indicating the methane is escaping from the sea.

The images below show methane levels recorded by the NPP satellite:
Jan. 6, 2019, with peak levels of 2513 ppb at 1000 mb, 2600 ppb at 840 mb and 2618 ppb at 695 mb;
Jan. 11, 2019, with peak levels of 2577 ppb at 1000 mb, 2744 ppb at 840 mb and 2912 ppb at 695 mb;
Jan. 15, 2019, with peak levels of 2524 ppb at 1000 mb, 2697 ppb at 840 mb and 2847 ppb at 695 mb.

















The images below show methane levels recorded by the MetOp satellites:
Jan. 15, 2019, with peak levels of 2177 ppb at 840 mb, 2342 ppb at 695 mb and 2541 ppb at 586 mb;
Jan. 16, 2019, with peak levels of 2219 ppb at 840 mb, 2299 ppb at 695 mb and 2475 ppb at 586 mb;
Jan. 19, 2019, with peak levels of 2201 ppb at 840 mb, 2489 ppb at 695 mb and 2813 ppb at 586 mb.
















The Importance of the Ozone Layer

Increases in stratospheric water vapor are bad news, as they speed up global warming and lead to loss of stratospheric ozone, as Drew Shindell pointed out back in 2001.

It has long been known that deterioration of the ozone shield increases ultraviolet-B irradiation, in turn causing skin cancer. Recent research suggest that, millions of years ago, it could also have led to loss of fertility and consequent extinction in plants and animals (see box right).

Nitrous oxide

As the left panel of the image below shows, growth in the levels of chlorofluorocarbons (CFCs) has slowed over the years, but their impact will continue for a long time, given their long atmospheric lifetime (55 years for CFC-11 and 140 years for CFC-12, CCl2F2).

Furthermore, as the right panel shows, the impact of nitrous oxide (N₂O) as an ozone depleting substance (ODS) has relatively grown, while N₂O levels also continue to increase in the atmosphere.

[ click on images to enlarge ]
Existential Threats

In conclusion, rising levels of emissions by people constitute existential threats in many ways. Rising temperatures cause heat stress and infertility, and there are domino effects. Furthermore, stratospheric ozone loss causes cancer and infertility.

Only once the ozone layer formed on Earth some 600 million years ago could multicellular life develop and survive. Further loss of stratospheric ozone could be the fastest path to extinction for humanity, making care for the ozone layer imperative.

As described in an earlier post, Earth is on the edge of runaway warming and in a moist-greenhouse scenario oceans evaporate into the stratosphere with loss of the ozone layer.

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


Links

• Climate and ozone response to increased stratospheric water vapor, by Drew Shindell (2001)
https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/1999GL011197

• Stratospheric ozone over the United States in summer linked to observations of convection and temperature via chlorine and bromine catalysis, by James Anderson et al. (2017)
https://www.pnas.org/content/114/25/E4905

• Harvard Speaks on Climate Change: James Anderson (2016)
https://vimeo.com/185794598

• Climate Week: Climate Science Breakfast with James Anderson (April 9, 2015)
http://environment.harvard.edu/climate-week-climate-science-breakfast-james-anderson

• 10°C or 18°F warmer by 2021?
https://arctic-news.blogspot.com/2017/04/10c-or-18f-warmer-by-2021.html

• Noctilucent clouds indicate more methane in upper atmosphere
https://arctic-news.blogspot.com/2012/09/noctilucent-clouds-indicate-more-methane-in-upper-atmosphere.html

• Noctilucent clouds: further confirmation of large methane releases
https://methane-hydrates.blogspot.com/2013/12/noctilucent-clouds-further-confirmation-of-large-methane-releases.html

• It could be unbearably hot in many places within a few years time
https://arctic-news.blogspot.com/2016/07/it-could-be-unbearably-hot-in-many-places-within-a-few-years-time.html

• Climate change: effect on sperm could hold key to species extinction, by Kris Sales
https://theconversation.com/climate-change-effect-on-sperm-could-hold-key-to-species-extinction-107375

• Climate change: effect on sperm could hold key to species extinction
https://theconversation.com/climate-change-effect-on-sperm-could-hold-key-to-species-extinction-107375

• UV-B–induced forest sterility: Implications of ozone shield failure in Earth’s largest extinction, by Jeffrey Benca et al. (2018)
http://advances.sciencemag.org/content/4/2/e1700618

• Co-extinctions annihilate planetary life during extreme environmental change, by Giovanni Strona and Corey Bradshaw (2018)
https://www.nature.com/articles/s41598-018-35068-1

• NOAA's Annual Greenhouse Gas Index
https://www.esrl.noaa.gov/gmd/aggi

• NOAA Study Shows Nitrous Oxide Now Top Ozone-Depleting Emission
https://www.esrl.noaa.gov/news/2009/nitrous_oxide_top_ozone_depleting_gas.html

• Earth is on the edge of runaway warming
https://arctic-news.blogspot.com/2013/04/earth-is-on-the-edge-of-runaway-warming.html

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



Monday, October 2, 2017

The Arctic is Changing the Jet Stream - Why This Is Important

By Sam Carana, with contributions by Jennifer Francis

Global warming is increasing the strength of hurricanes. A warmer atmosphere holds more water vapor and sea surface temperatures are rising. Both of these changes strengthen hurricanes. Steering winds may also be changing, causing unusual hurricane tracks such as Sandy's left turn into the mid-Atlantic seaboard and Harvey's stagnation over Houston. Is rapid Arctic warming playing a role?

Jennifer Francis has long been warning that global warming is increasing the likelihood of wavier jet stream patterns and more frequent blocking events, both of which have been observed. The Arctic is warming more rapidly than the rest of the world. The narrowing temperature difference between the Arctic and lower latitudes is weakening the speed at which the jet stream circumnavigates Earth and may be making the jet stream more wavy. In a 2012 study, Jennifer Francis and Stephen Vavrus warned that this makes atmospheric blocking events in the Northern Hemisphere more likely, aggravating extreme weather events related to stagnant weather conditions, such as drought, flooding, cold spells, and heat waves.

The danger was highlighted later that year, when a strong block associated with a deep jet stream trough helped steered Hurricane Sandy toward New York. In 2017, Hurricane Harvey hovered over Houston and dumped record-breaking rains (over 50 inches in some locations!), again highlighting this danger.

The jet stream separates cold air in the Arctic from warmer air farther south. A wavier jet stream transports more heat and moisture into the Arctic. This speeds up warming of the Arctic in a number of ways. In addition to warming caused by the extra heat, the added water vapor is a potent greenhouse gas, trapping more heat in the atmosphere over the Arctic, while it also causes more clouds to form that also are effective heat trappers.

As the Arctic keeps warming, the jet stream is expected to become more distorted, bringing ever more heat and moisture into the Arctic. This constitutes a self-reinforcing feedback loop that keeps making the situation worse. In conclusion, it's high time for more comprehensive and effective action to reduce the underlying culprit: global warming.


Jennifer Francis is Research Professor at the Institute of Marine and Coastal Sciences at Rutgers University, where she studies Arctic climate change and the link between the Arctic and global climates.

Jennifer has received funding from the National Science Foundation and NASA. She is a member of the American Meteorological Society, American Geophysical Union, Association for Women in Science and the Union of Concerned Scientists.


Links

• Evidence Linking Arctic Amplification to Extreme Weather in Mid-Latitudes, by Jennifer Francis and Stephen Vavrus (March 17, 2012)
http://onlinelibrary.wiley.com/doi/10.1029/2012GL051000/full

• Why Are Arctic Linkages to Extreme Weather Still Up in the Air? By Jennifer Francis (July 7, 2017)
http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-17-0006.1

• Amplified Arctic warming and mid‐latitude weather: new perspectives on emerging connections, by Jennifer Francis, Stephen Vavrus, Judah Cohen (May 16, 2017)
http://wires.wiley.com/WileyCDA/WiresArticle/wisId-WCC474.html

• Jennifer Francis: A New Arctic Feedback - Dec 2016 interview with Peter Sinclair (Jan 16, 2017)
https://www.youtube.com/watch?v=w_EzF4k9_QY

• Precipitation over the Arctic - by Sam Carana (27 Jan 2017)
https://www.youtube.com/watch?v=R_q3uWQR8Mw

• Jennifer Francis - Understanding the jet stream (26 Feb 2013)
https://www.youtube.com/watch?v=_nzwJg4Ebzo



Friday, January 27, 2017

Arctic Ocean Feedbacks


The world is warming rapidly, and the Arctic is warming much more rapidly than the rest of the world. In December 2016, the temperature anomaly from latitude 83°N to the North Pole was 8 times as high as the global anomaly. Above forecast for February 6, 2017, shows that temperatures over parts of the Arctic Ocean will be as much as 30°C or 54°F higher than they were in 1979-2000. How can it be so much warmer in a place where, at this time of year, little or no sunlight is shining? The Arctic Ocean is warming particularly rapidly due to a multitude of feedbacks, some of which are illustrated on the image below.


As the Arctic is warming more rapidly than the rest of the world, the temperature difference between the Arctic and the northern latitudes decreases, which makes the jet stream wavier. Jennifer Francis has written extensively about jet stream changes as a result of rapid warming in the Arctic. In the video below, Peter Sinclair interviews Jennifer Francis on these changes.


The changes to the jet stream make it easier for warm air from the south to enter the Arctic and for cold air to move out of the Arctic deep down into North America and Eurasia. At the same time, this also increases the temperature difference between the continents and the oceans, which is quite significant given the rapid warming of oceans across the globe. The result of the greater temperature difference between oceans and continents is that stronger winds are now flowing over the oceans along the jet stream tracks.

Stronger winds come with more evaporation and rain, which accumulates as freshwater at the surface of the North Atlantic and the North Pacific. The freshwater acts as a seal, as a lid on the ocean, making that less heat gets transferred from underneath the freshwater lid to the atmosphere. This makes that more heat can travel underneath the sea surface through the North Atlantic and reach the Arctic Ocean.


On January 28, 2017, sea surface temperature anomalies as high as 18.4°C (or 33.1°F) were showing up off the coast of Japan.


The situation is illustrated by above images, showing areas over the North Atlantic and the North Pacific (blue) where the sea surface was colder than it was in 1981-2011. Over these colder areas, winds are stronger due to the changes to the jet stream. On January 28, 2017, temperature anomalies were as high as 18.4°C (or 33.1°F) off the coast of Japan, while temperature anomalies were as high as 10.9°C (or 19.5°F) near Svalbard in the Arctic on January 27, 2017.

The image on the right shows sea surface temperature anomalies from 1971-2000.

The video below shows precipitation over the Arctic, run on January 27, 2017, and valid up to February 4, 2017.


Beaufort Gyre and Transpolar Drift
Changes to wind patterns can also affect sea currents in the Arctic Ocean such as the Beaufort Gyre and the Transpolar Drift. In the video below, at around 7:00, Paul Beckwith warns that further loss of sea ice will make these sea currents change direction, which in turn will draw more warm seawater from the North Atlantic into the Arctic Ocean.

As more ocean heat enters the Arctic Ocean and as sea ice retreats, more heat and water vapor will rise from the Arctic Ocean into the atmosphere over the Arctic. Increased water vapor will make it harder for heat to escape into space, i.e. more heat will remain trapped in the atmosphere and this will add to global warming.


The changes to the jet stream and the associated changes discussed above all lead to further warming of the Arctic Ocean, next to the warming caused by other feedbacks such as loss of albedo and loss of ice as a heat buffer. Together, sea ice loss and these associated feedbacks could cause global temperatures to rise by 1.6°C by 2026.

There are further feedbacks affecting the Arctic, as described at this page. One of the most dangerous feedbacks is methane escaping from the seafloor of the Arctic Ocean. As the temperature of the Arctic Ocean keeps rising, it seems inevitable that more and more methane will rise from its seafloor and enter the atmosphere, at first strongly warming up the atmosphere over the Arctic Ocean itself - thus causing further methane eruptions - and eventually warming up the atmosphere across the globe.

Above image paints a dire warning. The image shows that methane levels were as high as 2562 ppb on January 28, 2017. The image further shows high methane levels off the coast of Siberia and also where water from Nares Strait enters Baffin Bay.

Feedbacks and further elements of a potential temperature rise by 2026 of more than 10°C above prehistoric levels are further described at the extinction page.

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


Links

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

• Feedbacks
http://arctic-news.blogspot.com/p/feedbacks.html

• Extinction
http://arctic-news.blogspot.com/p/extinction.html

• 2016 well above 1.5°C
http://arctic-news.blogspot.com/2017/01/2016-well-above-1.5c.html

• Accelerating Warming of the Arctic Ocean
http://arctic-news.blogspot.com/2016/12/accelerating-warming-of-the-arctic-ocean.html


Friday, October 28, 2016

Arctic sea ice extent again at record low for time of year

For some time, Arctic sea ice extent has again been at a record low for the time of the year. The image below shows Arctic sea ice extent on October 26, 2016, when extent was only 6.801 million km².


One reason for the low sea ice extent is the high and rising temperature of the Arctic Ocean. On October 27, 2016, the Arctic Ocean was as warm as 14.8°C or 58.6°F (green circle near Svalbard), 12.1°C or 21.7°F warmer than 1981-2011, as the image below shows.


On October 29, 2016, the Arctic Ocean was as warm as 14.9°C or 58.8°F (green circle near Svalbard), 12.1°C or 21.8°F warmer than 1981-2011, as the image below shows.


As the sea ice shrinks, less sunlight gets reflected back into space, while more open water and higher sea surface temperatures also cause storms and cyclones to become stronger. Stronger cyclones also cause greater amounts of water vapor to move up the Pacific Ocean and the Atlantic Ocean toward the Arctic.

[ click on image to enlarge ]
[ click on image to enlarge ]
Less Arctic sea ice and a warmer Arctic Ocean make that more heat and water vapor gets transferred from the Arctic Ocean to the atmosphere. The two above images show temperature forecasts for November 1 & 2, 2016. In both cases, temperatures over the Arctic as a whole are forecast to be as much as 6.40°C higher than 1979-2000.

As these images show, temperature anomalies in many places are at the top end of the scale, i.e. +20°C or +36°F.


Above combination image shows record low Arctic sea ice for the time of the year (left) and near record low Antarctic sea ice for the time of the year (right), with a combined sea ice extent of only 23.751 million km² on October 28, 2016. In other words, the world is now absorbing a lot of sunlight that was previously reflected back into space.

Below are two further temperature forecast:

Above image shows forecasts for October 31, 2016. The Arctic is forecast to be 6.07°C warmer than 1979-2000, while the Antarctic is forecast to be 4.56°C warmer than 1979-2000.

Above image shows forecasts for November 1, 2016. The Arctic is forecast to be 6.42°C warer than 1979-2000, while the Antarctic is forecast to be 3.70°C warmer than 1979-2000.

Rising temperatures over the Arctic further contribute to a rise in the amount of water vapor in the air over the Arctic at a rate of 7% more water vapor for every 1°C warming. Since water vapor is a potent greenhouse gas, more water vapor further accelerates warming in the Arctic.

The Climate Reanalyzer image below shows the temperature rise in the Arctic over time.


In the video below, Dr. Walt Meier of NASA Goddard Space Flight Center describes how the Arctic has been losing its thicker and older sea ice over the years (1991 to September 2016).


The Naval Research Lab 30-day thickness animation below (up to October 28, 2016, with forecasts up to November 5, 2016) further shows minimal recent growth of the Arctic sea ice, especially in terms of the ice with a thickness of 1m or above.



As the Arctic Ocean gets warmer, the danger grows that large amounts of methane will erupt from destabilizing hydrates at its seafloor. Ominously, high methane levels are visible over the Arctic on the image below, showing methane levels as high as 2424 ppb on October 24, 2016.

The animation below, made with images from another satellite (and a different scale), shows high methane levels over th Arctic Ocean from October 26 to 28, 2016.


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


Monday, October 10, 2016

Blue Ocean Event September 2017?

Will there be a Blue Ocean Event in September 2017, during which the Arctic Ocean will be virtually ice-free? What would be the significance of such an event?

The Arctic Ocean is about to become virtually ice-free, perhaps as early as next year. At first, this Blue Ocean Event may last for one or more days in September 2017. Over the years, the ice-free period will grow longer and longer, if no action is taken.

Projections of an ice-free Arctic Ocean have been made for years. What makes the prospect of a Blue Ocean Event so dire?

Disappearance of the sea ice means that a huge amount of sunlight that was previously reflected back into space, is instead getting absorbed by the Arctic. The reason for this is that sea ice is more reflective than the water of the Arctic Ocean. The situation on land in the Arctic is similar, i.e. the snow and ice cover on land is more reflective than the darker soil and rocks that get uncovered as the snow and ice disappears. So, extra heat gets added and this is accelerating warming in the Arctic. On land, extra heat will also warm up water of rivers, and a lot of this heat will end up in the Arctic Ocean.

Another feedback is water vapor, as highlighted in the diagram below.


A warmer atmosphere carries more water vapor. Since water vapor is a potent greenhouse gas, this further accelerates warming over the Arctic.


As above image shows, temperatures have been more than 2.5°C warmer than 1981-2010 over most of the Arctic Ocean over the past 365 days (up to October 7, 2016). Accelerated Arctic warming has been taking place for a long time. So, what is it that makes a Blue Ocean Event, a virtually ice-free Arctic Ocean, such a big thing?

It is a huge event, because once the sea ice is gone, warming of the Arctic Ocean is likely to speed up even more dramatically. Why? Because having no more sea ice means that the buffer is gone. In the past, thick sea ice extended meters below the sea surface, in many parts of the Arctic Ocean. Melting of this ice into water did consume massive amounts of ocean heat. As such, thick sea ice acted as a buffer. Over the years, Arctic sea ice has become thinner and thinner, as illustrated by the image below.

[ click on image to enlarge ]
Over the past few years, trends have been pointing at zero thickness soon, i.e. in a matter of years. Added below is a trend produced by Arctische Pinguin, pointing at zero volume sea ice in the year 2021.
[ click on image to enlarge ]
Note that there is some variability from year to year. This indicates that a Blue Ocean Event may well happen earlier than the trend, e.g. in September 2017. The image further shows that there's hardly any buffer left, the buffer is virtually gone!

This buffer used to consume massive amounts of ocean heat that is carried along sea currents into the Arctic Ocean. Once the sea ice is gone, that heat must go somewhere else. A huge amount of energy used to be absorbed by this buffer, i.e. by melting ice and transforming it into water. The energy that used to be absorbed by melting ice is as much as it takes to warm up an equivalent mass of water from zero °C to 80 °C. Much of this heat will then suddenly speed up warming of the water of the Arctic Ocean, rather than going into melting the ice as it did previously. So, the water of the Arctic Ocean will suddenly warm up dramatically. Remember that the Arctic Ocean in many areas is very shallow, in many places it's less than 50 m deep, as discussed in an earlier post.

The Buffer has gone, feedback #14 on the Feedbacks page
The danger is that this extra heat will reach the seafloor and destabilize methane hydrates that are contained in sediments at the bottom of the Arctic Ocean. This could result in huge methane eruptions. It is hard for methane plumes to get broken down in the water, given the abrupt and concentrated nature of such releases and given that the Arctic Ocean is in so many places very shallow. Once that methane enters the atmosphere, it will strongly contribute to further warming of the atmosphere over the Arctic.


In conclusion, disappearance of the sea ice would mean that the buffer has gone. This further increases the danger of huge abrupt releases of methane from the seafloor of the Arctic Ocean. In many respects, the danger is such that we can just count ourselves lucky that such huge releases haven't occurred yet.

In response to this danger, comprehensive and effective action is needed, along multiple lines of action, each implemented in parallel and simultaneously. While local feebates are typically the most effective policies, local communities can each decide what works best for them, provided that agreed targets are met, and such targets will need to be a lot stronger and more comprehensive than the aspirational emission reductions that countries have submitted as part of the Paris Agreement.

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



Above post was also read by David Petraitis as part of the podcast by Wolfgang Werminghausen



Sunday, March 13, 2016

February Temperature


The February 2016 land and ocean temperature anomaly was 1.35°C (2.43°F) above the average temperature in the period from 1951 to 1980, as above image shows (Robinson projection).

On land, it was 1.68°C (3.02°F) warmer in February 2016, compared to 1951-1980, as the image below shows (polar projection).


The image below combines the above two figures in two graphs, showing temperature anomalies over the past two decades.


Below are the full graphs for both the land-ocean data and the land-only data. Anomalies on land during the period 1890-1910 were 0.61°C lower compared to the period from 1951 to 1980, which is used as a reference to calculate anomalies. The blue line shows land-ocean data, while the red line shows data from stations on land only.


At the Paris Agreement, nations committed to strengthen the global response to the threat of climate change by holding the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels.

To see how much temperatures have risen compared to pre-industrial levels, a comparison with the period 1951-1980 does not give the full picture. The image below compares the February 2016 temperatures with the period from 1890 to 1910, again for land only.


Since temperatures had already risen by ~0.3°C (0.54°F) before 1900, the total temperature rise on land in February 2016 thus is 2.6°C (4.68°F) compared to the start of the industrial revolution.

There are a number of elements that determine how much the total temperature rise on land will be, say, a decade from now:

Rise 1900-2016: In February 2016, it was 2.3°C (4.14°F) warmer on land than it was in 1890-1910.

Rise before 1900: Before 1900, temperature had already risen by ~0.3°C (0.54°F), as Dr. Michael Mann points out (see earlier post).

Rise 2016-2026: If levels of carbon dioxide and further greenhouse gases do keep rising, there will additional warming over the next ten years. Even with dramatic cuts in carbon dioxide emissions, temperatures can keep rising, as maximum warming occurs about one decade after a carbon dioxide emission, so the full wrath of the carbon dioxide emissions over the past ten years is still to come. Moreover, mean global carbon dioxide grew by 3.09 ppm in 2015, more than in any year since the record started in 1959, prompting an earlier post to add a polynomial trendline that points at a growth of 5 ppm by 2026 (a decade from now). This growth took place while global energy-related CO2 emissions have hardly grown over the past few years, indicating that land and oceans cannot be regarded as a sink, but should be regarded as source of carbon dioxide. On land, carbon dioxide may be released due to land changes, changes in agriculture, deforestation and extreme weather causing droughts, wildfires, desertification, erosion and other forms of soil degradation. Importantly, this points at the danger that such emissions will continue to grow as temperatures keep rising. New studies on permafrost melt (such as this one and this one) show that emissions and temperatures can rise much faster in the Arctic than previously thought. Furthermore, a 2007 study found a 25% soil moisture reduction to result in 2°C warming. Altogether, the rise over the next decade due to such emissions may be 0.2°C or 0.36°F (low) to 0.5°C or 0.9°F (high).

Removal of aerosols: With the necessary dramatic cuts in emissions, there will also be a dramatic fall in aerosols that currently mask the full warming of greenhouse gases. From 1850 to 2010, anthropogenic aerosols brought about a decrease of ∼2.53 K, says a recent paper. In addition, more aerosols are likely to be emitted now than in 2010, so the current masking effect of aerosols may be even higher. Stopping aerosol release may raise temperatures by 0.4°C or 0.72°F (low) to 2.5°C or 4.5°F (high) over the next decade, and when stopped abruptly this may happen in a matter of weeks.

Albedo change: Warming due to Arctic snow and ice loss may well exceed 2 W per square meter, i.e. it could more than double the net warming now caused by all emissions by people of the world, as Professor Peter Wadhams calculated in 2012. The temperature rise over the next decade due to albedo changes as a result of permafrost and sea ice decline may be 0.2°C or 0.36°F (low) to 1.6°C or 2.9°F (high).

Methane eruptions from the seafloor: ". . . we consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time," Dr. Natalia Shakhova et al. wrote in a paper presented at EGU General Assembly 2008. Authors found that such a release would cause 1.3°C warming by 2100. Such warming from an extra 50 Gt of methane seems conservative when considering that there now is only some 5 Gt of methane in the atmosphere, and over a period of ten years this 5 Gt is already responsible for more warming than all the carbon dioxide emitted by people since the start of the industrial revolution. The temperature rise could be higher, especially in case of large abrupt release, but in case of small and gradual releases much of the methane may be broken down over the years. The temperature rise due to seafloor methane over the next decade may be 0.2°C or 0.36°F (low) to 1.1°C or 2°F (high).

Water vapor feedback:
 "Water vapour feedback acting alone approximately doubles the warming from what it would be for fixed water vapour. Furthermore, water vapour feedback acts to amplify other feedbacks in models, such as cloud feedback and ice albedo feedback. If cloud feedback is strongly positive, the water vapour feedback can lead to 3.5 times as much warming as would be the case if water vapour concentration were held fixed", according to the IPCC. In line with the above elements, this may result in a temperature rise over the next decade of 0.2°C or 0.36°F (low) to 2.1°C or 3.8°F (high).

The image below puts all these elements together in two scenarios, one with a relatively low temperature rise of 3.9°C (7.02°F) and another one with a relatively high temperature rise of 10.4°C (18.72°F).


Note that the above scenarios assume that no geoengineering will take place.

The 2.3°C warming used in above image isn't the highest figure offered by the NASA site. An even higher figure of 2.51°C warming can be obtained by selecting a 250 km smoothing radius for the on land data.

When adding the 0.3°C that temperatures rose before 1900, the rise from the start of the industrial revolution is 2.81°C (5.06°F), as illustrated by the image on the right.

The image also shows that this is the average rise. At specific locations, it is as much as 16.6°C (30°F) warmer than at the start of the industrial revolution.

Furthermore, temperatures are higher on the Northern Hemisphere than on the Southern Hemisphere. This is illustrated by the image below showing NASA temperature anomalies for January 2016 (black) and February 2016 (red) on land on the Northern Hemisphere. The data show that it was 2.36°C (4.25°F) warmer in February 2016 compared to 1951-1980.


How much of the rise can be attributed to El Niño? The added trendlines constitute one way to handle variability such as caused by El Niño and La Niña events and they can also indicate how much warming could be expected to eventuate over the years to come.

The February trendline also indicates that the temperature was 0.5°C lower in 1900 than in 1951-1980, so the total rise from 1900 to February 2016 is 2.86°C (5.15°F). Together with a 0.3°C rise before 1900, this adds up to a rise on land on the Northern Hemisphere of 3.16°C (5.69°F) from pre-industrial levels to February 2016. Most people on Earth live on land on the Northern Hemisphere. In other words, most people are already exposed to a temperature rise that is well above any guardrails that nations at the Paris Agreement pledged would not be crossed.


Temperatures may actually rise even more rapidly than these trendlines indicate. As above image illustrates, the largest temperature rises are taking place in the Arctic, resulting in a rapid decline of snow and ice cover and increasing danger that large methane eruptions from the seafloor will take place, as illustrated by the image on the right, from an earlier post. This could then further lead to more water vapor, while the resulting temperature rises also threaten to cause more droughts, heatwaves and wildfires that will cause further emissions, as well as shortages of food and fresh water supply in many areas.

Adding the various elements as discussed above indicates that most people may well be hit by a temperature rise of 4.46°C or 8.03°F in a low rise scenario and of 10.96°C or 19.73°F in a high rise scenario, and that would be in one decade from February 2016. Since it is now already March 2016, that is less than ten years from now.

The image below shows highest mean methane readings on one day, i.e. March 10, over four years, i.e. 2013, 2014, 2015 and 2016, at selected altitudes in mb (millibar). The comparison confirms that the increase of methane in the atmosphere is more profound at higher altitudes, as discussed in earlier posts. This could indicate that methane from the Arctic Ocean is hardly detected at lower altitudes, as it rises in plumes (i.e. very concentrated), while it will then spread and accumulate at higher altitudes and at lower latitudes.


The conversion table below shows the altitude equivalents in mb, feet and m.

57016 feet44690 feet36850 feet30570 feet25544 feet19820 feet14385 feet 8368 feet1916 feet
17378 m13621 m11232 m 9318 m 7786 m 6041 m 4384 m 2551 m 584 m
 74 mb 147 mb 218 mb 293 mb 367 mb 469 mb 586 mb 742 mb 945 mb

Meanwhile Arctic sea ice area remains at a record low for the time of the year, as illustrated by the image below.


Next to rising surface temperatures in the Arctic, ocean temperature rises on the Northern Hemisphere also contribute strongly to both Arctic sea ice decline and methane releases from the seafloor of the Arctic Ocean, so it's important to get an idea how much the Northern Hemisphere ocean temperature can be expected to rise over the next decade. The NOAA image below shows a linear trend over the past three decades that is rising by 0.19°C per decade.

The image below, using the same data, shows a polynomial trend pointing at a 1.5°C rise in ocean temperature on the Northern Hemisphere over the next decade.


Below is another version of above graph.


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