Wet Bulb Globe Temperature Tipping Point

High Wet Bulb Globe Temperatures (WBGT) are forecast to hit Louisiana, United States, over the next few days. The image below shows a forecast for August 2, 2023, 18 UTC, with WBGT as high as 35°C forecast for a location 10 miles South East of Abbeville, Louisiana, U.S.

WBGT is a measure used by weather.gov to warn about expected heat stress when in direct sunlight. It takes into account the effect of temperature, relative humidity, wind speed, and solar radiation on humans.

As temperatures and humidity levels keep rising, a tipping point can be reached where the wind factor no longer matters, in the sense that wind can no longer provide cooling. The human body can cool itself by sweating, which has a physiological limit that was long described as a 35°C wet-bulb temperature. Once the wet-bulb temperature reaches 35°C, one can no longer lose heat by perspiration, even in strong wind, but instead one will start gaining heat from the air beyond a wet-bulb temperature of 35°C.

Accordingly, a 35°C wet-bulb temperature (equal to 95°F at 100% humidity or 115°F at 50% humidity) was long seen as the theoretical limit, the maximum a human could endure.

A 2020 study (by Raymond et al.) warns that this limit could be regularly exceeded with a temperature rise of less than 2.5°C (compared to pre-industrial). A 2018 study (by Strona & Bradshaw) indicates that most life on Earth will disappear with a 5°C rise. Humans, who depend for their survival on many other species, will likely go extinct with a 3°C rise, as illustrated by the image below, from an earlier post.

A 2022 study (by Vecellio et al.) finds that the actual limit is lower — about 31°C wet-bulb or 87°F at 100% humidity — even for young, healthy subjects. The temperature for older populations, who are more vulnerable to heat, is likely even lower. In practice the limit will typically be lower and depending on circumstances could be as low as a wet-bulb temperature of 25°C.

The above image shows a Wet Bulb Globe Temperature of 35°C (95°F) forecast for August 11, 2023, 19 UTC, for a location near Baton Rouge, Louisiana, U.S. 

Heat is the leading cause of weather-related deaths in the United States, as illustrated by the above image (credit: NOAA). Heat fatalities may be conservative figures. Recent research finds that where heat is being listed as an official cause of death, this likely underestimates the full toll of these events. Extreme heat can trigger heart attacks and strokes. In addition, some heart disease risk factors, such as diabetes—as well as heart medications, such as diuretics and beta blockers—can affect a person’s ability to regulate their body temperature and make it difficult to handle extreme heat. The study finds that extreme heat accounted for about 600-700 additional deaths from cardiovascular disease annually. A recent study estimates that extreme heat accounted for 12,000 premature deaths in the contiguous U.S. from 2000 to 2010, and a recent analysis calculates that the summer 2022 heatwave killed 61,000 people in Europe alone. 

The image below shows a temperature (°F) forecast for August 1, 2023, from Climate Reanalyzer. 

The video below discusses this.

Misery Index

The image below show a high reading on the 'Misery Index', the perceived ('feels like') temperature that is used by nullschool.net, combining wind chill and the heat index (which in turn combines air temperature and relative humidity, in shaded areas). A Misery Index temperature of 56.1°C or 133.1°F was recorded at a location off the coast of the United Arab Emirates (green circle) on August 5, 2023.

The temperature at that location at the time was 35.2°C or 95.4°F, lower than the temperature on the land surrounding the Gulf, but the relative humidity at that spot over the water was 78%, and that combination led to this very high 'feels like' temperature. 

This constitutes a warning. The sea, rivers and lakes are traditionally seen as places to go to, to cool off. However, high temperatures combined with high humidity over water bodies can result in conditions that go beyond what humans can bear. 

Climate change danger assessment

The image below, earlier discussed here, expands risk assessment beyond its typical definition as the product of the severity of impact and probability of occurrence, by adding a third dimension: timescale, in particular imminence.

Imminence alone could make that the danger constituted by rising temperatures needs to be acted upon immediately, comprehensively and effectively. While questions may remain regarding probability, severity and timescale of the dangers associated with climate change, the precautionary principle should prevail and this should prompt for action, i.e. comprehensive and effective action to reduce damage and improve the situation is imperative and must be taken as soon as possible.

Rapidly rising temperatures constitute tipping points in several ways 

Firstly, there is a biological threshold beyond which rising temperatures become lethal for humans, as discussed above. 

Secondly, as Gerardo Ceballos describes in the video below and in a 2017 analysis, there is a biological tipping point that threatens annihilation of species via the ongoing sixth mass extinction. Researchers such as Gerardo Ceballos (2020), Kevin Burke (2018) and Ignation Quintero (2013) have for years warned that mammals and vertebrates cannot keep up with the rapid rise in temperature. Humans are classified as vertebrate mammals, indicating that we will not avoid the fate of extinction, Guy McPherson (2020) adds. 

Thirdly, there are further tipping points, e.g. social-political ones. On the one hand, it would be good if people became more aware, as this could prompt more people into supporting the necessary action. On the other hand, as temperatures keep rising, there is also a danger that panic will break out, dictators will grab power and civilization as we know it will collapse abruptly, as warned about earlier, e.g. in 2007.  

Conclusion

In conclusion, to combat rising temperatures, transforming society is needed urgently, along the lines of this 2022 post in combination with declaration of a climate emergency.

Links

• Wet Bulb Globe Temperature
https://digital.mdl.nws.noaa.gov

• National Weather Service - Wet Bulb Globe Temperature: How and when to use it
https://www.weather.gov/news/211009-WBGT

• The emergence of heat and humidity too severe for human tolerance - by Colin Raymons et al. (2020)
https://www.science.org/doi/10.1126/sciadv.aaw1838

• Brief periods of dangerous humid heat arrive decades early
https://www.climate.gov/news-features/featured-images/brief-periods-dangerous-humid-heat-arrive-decades-early

• Evaluating the 35°C wet-bulb temperature adaptability threshold for young, healthy subjects (PSU HEAT Project) - by Daniel Vecellio et al. (2022)
https://journals.physiology.org/doi/full/10.1152/japplphysiol.00738.2021
Discussed at: https://www.facebook.com/groups/arcticnews/posts/10159973158374679

• NOAA - Weather Fatalities 2022
https://www.weather.gov/hazstat

• The Effects of Heat Exposure on Human Mortality Throughout the United States - by Drew Shindell (2021)

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019GH000234

• Heat-related mortality in Europe during the summer of 2022 - by Joan Ballester et al.
https://www.nature.com/articles/s41591-023-02419-z

Discussed at: https://www.facebook.com/groups/arcticnews/posts/10160875637104679

• As Temperatures Spike, So Do Deaths from Heart Disease (2022 News release)
https://www.acc.org/About-ACC/Press-Releases/2022/03/22/20/06/As-Temperatures-Spike-So-Do-Deaths-from-Heart-Disease

• Association of Extreme Heat and Cardiovascular Mortality in the United States: A County-Level Longitudinal Analysis From 2008 to 2017 - by Sameed Khatana et al. (2022)
https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.122.060746

• 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
Discussed at: https://www.facebook.com/groups/arcticnews/posts/10156903792219679

• When will we die?
https://arctic-news.blogspot.com/2019/06/when-will-we-die.html

• Climate Reanalyzer - Hourly Forecast Maps
https://climatereanalyzer.org/wx/fcst/?mdl_id=nam&dm_id=conus-lc&wm_id=t2

• PBS video - Too HOT and HUMID to Live: Extreme Wet Bulb Events are on the Rise 
https://www.pbs.org/video/too-hot-and-humid-to-live-extreme-wet-bulb-events-are-on-th-fazocs

• Nullschool
https://earth.nullschool.net

• How agriculture hastens species extinction | 60 Minutes (CBS News) | Gerardo Ceballos
https://www.youtube.com/watch?app=desktop&v=f21WWocqR-c

• Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines - by Gerardo Ceballos, Paul R. Ehrlich and Rodolfo Dirzo (2017)
https://www.pnas.org/content/114/30/E6089

• Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction - by Gerardo Ceballos, Paul Ehrlich, and Peter Raven (2020)
https://www.pnas.org/content/early/2020/05/27/1922686117

Discussed at: https://www.facebook.com/groups/arcticnews/posts/10158460232764679

• Rates of projected climate change dramatically exceed past rates of climatic niche evolution among vertebrate species - by Ignatio Quintero et al. (2013) 

https://onlinelibrary.wiley.com/doi/abs/10.1111/ele.12144

• Pliocene and Eocene provide best analogs for near-future climates - by Kevin Burke et al. (2018)
https://www.pnas.org/doi/10.1073/pnas.1809600115

Discussed at: https://www.facebook.com/groups/arcticnews/posts/10156972951354679

• Earth is in the Midst of Abrupt, Irreversible Climate Change - by Guy McPherson (2020)
https://www.onlinescientificresearch.com/articles/earth-is-in-the-midst-of-abrupt-irreversible-climate-change.pdf

Discussed at: https://www.facebook.com/groups/arcticnews/posts/10160004947844679

• Ten Dangers of Global Warming
https://arctic-news.blogspot.com/p/ten-dangers-of-global-warming.html

• Extreme heat stress

https://arctic-news.blogspot.com/2023/06/extreme-heat-stress.html

• Transforming Society
https://arctic-news.blogspot.com/2022/10/transforming-society.html

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

• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html

Extreme heat stress

Heatwaves

High Wet Bulb Globe Temperature (WBGT) is forecast to hit the Southeastern United States over the next few days. The image below shows a forecast for June 29, 2023, 18 UTC with WBGT as high as 34°C (93°F) forecast for a location near Jackson, Mississippi, U.S. 

[ click on images to enlarge ]

WBGT is a measure used by weather.gov to warn about expected heat stress when in direct sunlight. It estimates the effect of temperature, relative humidity, wind speed, and solar radiation on humans using a combination of temperatures from three thermometers:

• A Wet bulb measures the temperature read by a thermometer covered in a wet cloth. As water evaporates from the cloth, evaporation cools the thermometer. This mirrors how the human body cools itself with sweat.
• A black globe is used to measure solar radiation. Solar radiation heats the globe and wind blowing across it cools the globe.
• A Dry bulb calculates the air temperature measured in the shade. It is the temperature you would see on your thermometer outside.

The images on the right earlier featured in a 2016 post. 

The top image, an animation from the EPA, illustrates that a relatively small rise in average temperature can have a huge impact and result in a lot more hot weather as well as in even more extreme hot weather.

[ from earlier post ]

The three images underneath, from the IPCC, show the effect on extreme temperatures when (a) the mean temperature increases, (b) the variance increases, and (c) when both the mean and variance increase for a normal distribution of temperature.

The thermodynamic wet-bulb temperature is determined by temperature, humidity and pressure (hPa), and it is the lowest temperature that can be achieved by evaporative cooling of a water-wetted ventilated surface.

As temperatures and humidity levels keep rising, there comes a point where the wind factor no longer matters, in the sense that wind can no longer provide cooling.

The human body can cool itself by sweating, which has a physiological limit that was long described as a 35°C wet-bulb temperature. Once the wet-bulb temperature reaches 35°C, one can no longer lose heat by perspiration, even in strong wind, but instead one will start gaining heat from the air beyond a wet-bulb temperature of 35°C. 

Accordingly, a 35°C wet-bulb temperature (equal to 95°F at 100% humidity or 115°F at 50% humidity) was long seen as the theoretical limit, the maximum a human could endure. 

A 2020 study (by Raymond et al.) warns that this limit could be regularly exceeded with a temperature rise of less than 2.5°C (compared to pre-industrial). A 2018 study (by Strona & Bradshaw) indicates that most life on Earth will disappear with a 5°C rise. Humans, who depend for their survival on many other species, will likely go extinct with a 3°C rise, as illustrated by the image below, from an earlier post.

A 2022 study (by Vecellio et al.) finds that the actual limit is lower — about 31°C wet-bulb or 87°F at 100% humidity — even for young, healthy subjects. The temperature for older populations, who are more vulnerable to heat, is likely even lower. In practice the limit will typically be lower and depending on circumstances could be as low as a wet-bulb temperature of 25°C.

The images below show high readings on the 'Misery Index', the perceived temperature that is used by nullschool.net, combining wind chill and the heat index (which in turn combines air temperature and relative humidity, in shaded areas).

The image below shows a forecast for June 29, 2023 20 UTC, with weather conditions prolonged by circular wind patterns at 250 hPa (Jet Stream), while the Jet Stream is crossing the Equator (bottom left). Temperatures as high as 39.9°C (103.7°F) combined with a relative humidity of 35% result in perceived temperatures as high as 45°C (112.9°F) at the green circle.

As it turned out, the perceived temperature was as high as 44.9°C or 112.7°F on June 29, 2023 19 UTC, due to a 39.1°C or 102.5°F temperature and a 38% relative humidity at the surface, and with conditions prolonged by a distorted Jet Stream (at 250 hPa), with circular wind patterns and winds crossing the Equator.

The image below shows high readings on the 'Misery Index' for parts of Pakistan. On June 22, 2023, an air temperature of 45.4°C (113.7°F) and a relative humidity of 25% resulted in a perceived temperature of 51°C (123.7°F) at the area marked by the green circle. 

The above image also shows the Jet Stream (wind at 250 hPa). Distortion of the Jet Stream can lead to circular wind patterns that amplify heatwaves. As temperature rise, the temperature difference between the Equator and the Arctic narrows, distorting the Jet Stream resulting in more extreme  weather.

Perceived (feels like) air temperatures as high as 53.1°C or 127.7°F were recorded in Pakistan on July 4, 2023, 09 UTC (at green circle), with a 46.7°C or 116.1°F temperature and a 24% relative humidity recorded at the surface. Also, Jet Stream deformation shows up (at 250 hPa), with circular wind patterns and wind crossing the Equator (at the image bottom).

Meanwhile, heatwave conditions have also been affecting China, Texas and Mexico recently, with all-time high temperature records broken in each of these places. 

The press release of a 2022 Unicef report has the title 559 million children currently exposed to high heatwave frequency, rising to all 2.02 billion children globally by 2050. 

Fire and smoke from fires

An additional hazard is fire and the smoke from fires. The image below shows biomass-burning aerosols from fires in Canada extending over the North Atlantic on June 25, 2023, 03 UTC.

The forecast for June 29, 2023 21 UTC below shows remnants of the Canadian forest fires reaching Western Europe.

Feedbacks

As temperatures rise, fire and smoke hazards increase due to self-reinforcing feedback loops, including: 

• 

  [ Two out of numerous feedbacks ]

  Albedo loss and Jet Stream distortion:
  - as sea ice melts away and gets covered by meltpools and rainwater pools, soot, dust, and algae, the resulting albedo loss further pushes up temperatures
  - the narrowing temperature difference between the Arctic and the Tropics causes Jet Stream distortion, resulting in more extreme weather, incl. stronger storms that come with more lightning and can carry more oxygen to fires and spread fires faster and wider, and more intense heatwaves that can dramatically push up local temperatures, further intensifying droughts and forest fires
• a further self-reinforcing feedback loop is that water that was previously present in the soil, is increasingly moving up into the atmosphere, as the atmosphere sucks up more water vapor (7% more water vapor for every 1°C in temperature rise ), resulting in:
  - less evapotranspiration from vegetation, in turn resulting in less clouds and rain, thus pushing up temperatures and drying out soil and vegetation even more
  - erosion and less healthy vegetation that is more vulnerable to pests and diseases such as bark beetles, resulting in an increase in dead trees providing more fuel for fires

[ from earlier post ]

The image on the right, from a news release associated with a 2022 study, shows changes in atmospheric thirst, measured in terms of reference evapotranspiration from 1980-202 (in mm).

As temperatures rise due to people's emissions, more evaporation will take place over both land and oceans, but not all water will return as precipitation, so more water vapor will stay in the air and droughts affecting the soil and vegetation will intensify.

[ from earlier post ]

Water in the soil acts as a buffer, slowing down the temperature rise, so drier soil will heat up faster and further, causing land surface temperatures to rise even more and amplifying the impact of Urban heat island and Heat dome phenomena.

The image on the right, adapted from ESA, shows land surface temperatures as high as 65°C (149°F) in India on April 26, 2022. Note that land surface temperatures can be substantially higher than air temperatures.

The Copernicus image below shows Spain on 11 July 2023, where the Land Surface Temperature (LST), i.e. the temperature of the soil, in some areas of Extremadura (Spain) exceeded 60°C or 140°F, as measured by the Sea and Land Surface Temperature Radiometer (SLSTR) instrument, a feature of the Copernicus Sentinel-3 satellites. 

How high could temperatures rise?

The image below, from NASA, shows that February 2016 was 3.24°C or 5.83°F hotter on land than 1850-1890. Note that 1850-1890 is not pre-industrial, while the 2016 peak was reached during an El Niño, which raises the question how much hotter than pre-industrial it will be at the peak of the current El Niño. 

The image below says it even more poignantly: Looking at global averages over long periods is a diversion, peak temperature rise is the killer!

The above image shows that February 2016 was 3.28°C (5.904°F) hotter than 1880-1896 on land, and 3.68°C (6.624°F) hotter compared to February 1880 on land.

World temperature was at a new record high of 17.18°C or 62.92°F on July 4, 2023 (black). Both in 2022 (orange) and in 2016 (grey), the temperature reached 16.92°C or 62.46°F (on July 24, 2022 and August 13+14, 2016). The year 2016 is important, since it was a strong El Niño year and we're now again in an El Niño.

A 2023 study led by Tao Lian predicts the current El Niño to be strong. Moving from the bottom of a La Niña to the peak of a strong El Niño could make a difference of more than half a degree Celsius, as discussed in an earlier post.

Additionally, the June 2023 number of sunspots is more than twice as high as predicted, as illustrated by the image on the right, adapted from NOAA.

Furthermore, the 2022 Tonga submarine volcano eruption did add a huge amount of water vapor to the atmosphere, as discussed in an earlier post.

Alarm bells have been ringing for many years. As an example, the image below featured in a 2015 post, showing non-linear trends including a polynomial trendline (1: blue) pointing at global temperature anomalies of over 4°C by 2060. 

Moreover, a polynomial trend for the Arctic (2: red) threatens to cause major feedbacks to kick in, triggering runaway global warming (3: white) that looks set to catch up with accelerated warming in the Arctic and result in global temperature anomalies of 16°C by 2052.

[ from a 2015 post, click on image to enlarge ]

In the 2019 video below, Roger Hallam talks with Stephen Sackur from the BBC's HardTalk series. 

Climate change danger assessment

The image below, earlier discussed here, expands risk assessment beyond its typical definition as the product of the severity of impact and probability of occurrence, by adding a third dimension: timescale, in particular imminence.

Conclusion

Imminence alone could make that the danger constituted by rising temperatures needs to be acted upon immediately, comprehensively and effectively. While questions may remain regarding probability, severity and timescale of the dangers associated with climate change, the precautionary principle should prevail and this should prompt for action, i.e. comprehensive and effective action to reduce damage and improve the situation is imperative and must be taken as soon as possible. To combat rising temperatures, transforming society is needed, along the lines of this 2022 post in combination with declaration of a climate emergency.

[ image from Climate Emergency Declaration ]

Accordingly, everyone is encouraged to support and share this Climate Emergency Declaration.

Links

• Wet Bulb Globe Temperature
https://digital.mdl.nws.noaa.gov

• National Weather Service - Wet Bulb Globe Temperature: How and when to use it
https://www.weather.gov/news/211009-WBGT

• Nullschool.net
https://earth.nullschool.net

• Weather tracker: China issues heatstroke alert amid historic heatwave
https://www.theguardian.com/environment/2023/jun/23/weather-tracker-china-issues-heatstroke-alert-amid-historic-heatwave

• Peaks matter
https://arctic-news.blogspot.com/2018/08/peaks-matter.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

• The emergence of heat and humidity too severe for human tolerance - by Colin Raymons et al. (2020)
https://www.science.org/doi/10.1126/sciadv.aaw1838

• Brief periods of dangerous humid heat arrive decades early

https://www.climate.gov/news-features/featured-images/brief-periods-dangerous-humid-heat-arrive-decades-early

• Evaluating the 35°C wet-bulb temperature adaptability threshold for young, healthy subjects (PSU HEAT Project) - by Daniel Vecellio et al. (2022) 

https://journals.physiology.org/doi/full/10.1152/japplphysiol.00738.2021
Discussed at: https://www.facebook.com/groups/arcticnews/posts/10159973158374679

• 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

• Jet Stream
https://arctic-news.blogspot.com/p/jet-stream.html

• When Will We Die?
https://arctic-news.blogspot.com/2019/06/when-will-we-die.html

• Copernicus - Biomass-burning aerosols
https://atmosphere.copernicus.eu/charts/packages/cams/products/aerosol-forecasts

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

• Will there be Arctic sea ice left in September 2023?
https://arctic-news.blogspot.com/2023/05/will-there-be-arctic-sea-ice-left-in-september-2023.html

• Clausius–Clapeyron relation
https://en.wikipedia.org/wiki/Clausius–Clapeyron_relation

• Urban heat island
https://en.wikipedia.org/wiki/Urban_heat_island

• Heat dome
https://en.wikipedia.org/wiki/Heat_dome

• ESA - Heatwave across India
https://www.esa.int/ESA_Multimedia/Images/2022/04/Heatwave_across_India

• Evaporative Demand Increase Across Lower 48 Means Less Water Supplies, Drier Vegetation, and Higher Fire Risk
https://www.drought.gov/news/evaporative-demand-increase-across-lower-48-means-less-water-supplies

• A Multidataset Assessment of Climatic Drivers and Uncertainties of Recent Trends in Evaporative Demand across the Continental United States - by Christine Albano et al. (2022)

https://journals.ametsoc.org/view/journals/hydr/23/4/JHM-D-21-0163.1.xml

• Carbon dioxide crosses 422 ppm

https://arctic-news.blogspot.com/2022/04/carbon-dioxide-crosses-422-ppm.html

• 559 million children currently exposed to high heatwave frequency, rising to all 2.02 billion children globally by 2050

https://www.unicef.org/press-releases/heatwaves-report

• Copernicus - Scorching heatwave hits Spain 
https://www.copernicus.eu/en/media/image-day-gallery/scorching-heatwave-hits-spain

• NASA - custom plots 
https://data.giss.nasa.gov/gistemp/graphs_v4/customize.html

• Climate Reanalyzer - World Daily 2-meter Air Temperature (90-90°N, 0-360°E)
https://climatereanalyzer.org/clim/t2_daily

• NOAA - Solar cycle sunspot number progression
https://www.swpc.noaa.gov/products/solar-cycle-progression

• A Strong 2023/24 El Niño is Staged by Tropical Pacific Ocean Heat Content Buildup - by Tao Lian et al. (2023)

https://spj.science.org/doi/10.34133/olar.0011

• Transforming Society
https://arctic-news.blogspot.com/2022/10/transforming-society.html

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

• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html

More and more extreme weather

The weather is getting more and more extreme. On April 23, 2016, temperatures in India were as high as 47.7°C or 117.9°F. At the same time, temperatures in California were as low as -12.6°C or 9.2°F, while temperatures in Greenland were as high as 3.6°C or 38.6°F. Meanwhile, Antarctica was as cold as -60°C or -76°F.

The situation in India is most worrying. Temperatures are very high in many locations. India has been experiencing heatwave conditions for some time now, as reported in this and in this earlier posts.

[ click on images to enlarge ]

More extreme weather goes hand in hand with changes that are taking place to the jet stream, as also discussed in earlier posts (see further below).

As the Arctic warms up more rapidly than the rest of the world, the temperature difference between the Equator and the North Pole decreases, which in turn weakens the speed at which the north polar jet stream circumnavigates the globe. This is illustrated by the wavy patterns of the north polar jet stream in the image on the right.

The outlook for the next week shows the north polar jet stream move higher over the arctic, and to eventually disintegrate altogether, while merging with the subtropical jet stream over the Pacific Ocean.

The video below shows how a very wavy jet stream is projected to disintegrate over the Arctic Ocean over the coming week.

This makes it easier for warm air to move into the Arctic and for cold air to move out of the Arctic, in turn further decreasing the temperature difference between the Equator and the North Pole, in a self-reinforcing feedback loop: "It's like leaving the freezer door open."

Temperature forecasts for the Arctic Ocean are high, with anomalies projected to be above 4°C for the Arctic over the coming week.

The image on the right shows one such forecast, projecting a temperature anomaly of 5.31°C or 9.56°F for the Arctic on April 27, 2016, 1500 UTC, while an earlier forecast projected a 5.34°C or 9.61°F anomaly (hat tip to Mark Williams).

The danger is that the combined impact of high air temperatures and ocean heat will cause rapid demise of Arctic sea ice over the next few months.

On April 22, 2016, the sea surface was as much as 11.3°C or 20.3°F warmer than 1981-2011 (at the location off the coast of North America marked by the green circle).

High ocean heat is further accelerating Arctic sea ice demise, as the Gulf Stream keeps carrying ever warmer water into the Arctic Ocean. The image below, created with an image from the JAXA site, shows that Arctic sea ice extent was well under 13 million km² on April 19, 2016, and about 1 million km²  less than the extent in the year 2012 around this time of year.

Demise of the sea ice will cause even more rapid warming of the Arctic Ocean, with the danger that more heat will penetrate sediments that contain huge amounts of methane in the form of hydrates and free gas, threatening to trigger huge methane releases and cause runaway warming.

Methane levels are increasing strongly. This may not be as noticeable when taking samples from ground stations, but the rise is dramatic at higher altitudes, as also discussed earlier in this post and in this post.

Methane levels in ppb (parts per billion, at bottom of image)

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


Related

- What's wrong with the weather?

http://arctic-news.blogspot.com/2014/07/whats-wrong-with-the-weather.html

- How melting Arctic ice is driving harsh winters - by Nick Breeze
http://arctic-news.blogspot.com/2014/11/how-melting-arctic-ice-is-driving-harsh.html

- Wild Weather Swings 

http://arctic-news.blogspot.com/2014/10/wild-weather-swings.html

- Record Arctic Warming
http://arctic-news.blogspot.com/2016/04/record-arctic-warming.html

2015 warmest year on record

1.1°C or 34.1°F at the North Pole

The year 2015 is shaping up to be the warmest year on record. In the media, a lot of attention has been given to the many floods, droughts, wildfires and heatwaves that have battered the world this year.

Sadly, though, little attention is given to the situation in the Arctic. The image on the right shows a forecast for December 30, 2015, with temperatures at the North Pole above freezing point, as further illustrated by the nullschool.net image below, showing a temperature forecast of 1.1°C or 34.1°F for the North Pole. Wind speed at the North Pole is forecast to be 105 mph or 168 km/h on December 30, 2015, and 133 mph or 215 km/h closer to Svalbard.

As the image below illustrates, very high temperatures are forecast to hit the Arctic Ocean on December 30, 2015.

Above image shows temperature anomalies at the highest end of the scale for most of the Arctic Ocean, with a temperature anomaly for the Arctic as a whole of 2.4°C or 4.32°F above what was common in 1979-2000. The situation isn't likely to improve soon. For January 3, 2016, the temperature in the Arctic is forecast to be as much as 4.56°C or 8.21°F warmer.

How is it possible for such high temperatures to occur over the Arctic Ocean? The image below shows how the year 2015 is shaping up in terms of temperature anomalies.

Global warming is felt most strongly in the Arctic as warming continues, as illustrated by above image and by the image on the right.

Warming in the Arctic is accelerating due to feedbacks. One of these feedbacks is the way the jet streams are changing. Changes in the jet streams are becoming more prominent as the Arctic is warming up more rapidly than the rest of the world.

jet streams

As the difference in temperature between the Arctic and the equator becomes smaller, the speed at which the jet stream circumnavigates the globe is decreasing and jet streams become more wavy.

Meanwhile, most of the extra heat caused by global warming goes into the oceans, and the Atlantic Ocean is warming up fast. At the same time, meltwater is accumulating at the surface of the North Atlantic, lowering sea surface temperatures there. With such large differences between high temperatures over North America and lower temperatures over the North Atlantic, the speed of the jet stream between those places can increase dramatically.

The result is that huge amounts of warm air are being pushed high into the Arctic. The image on the right shows the jet streams on December 27, 2015, when speeds as high as 263 mph or 424 km/h were reached at the location marked by the green circle. Also note the jet streams crossing the Arctic at the top of the image, while crossing the equator at the bottom of the image.

The image below shows sea surface temperature anomalies on the Northern Hemisphere in November.

For over a month now, storms over the North Atlantic have been pushing hot air high up into the Arctic. The video below uses surface wind content by Climate Reanalyzer (selected daily averages and sequences of forecasts) to cover the period from December 5, 2015, to January 8, 2016.

Best wishes for 2016

Above video stops at January 8, 2016, when two cyclones are visible, one in the North Atlantic and another one over the North Pacific, prompting me to create the image on the right.

What causes these storms to grow this strong? Waters keeps warming up dramatically off the east coast of North America. Emissions from North America tend to extend over these waters, due to the Coriolis effect, and this contributes to their extreme warming.

The image below shows carbon dioxide levels as high as 511 ppm over New York on November 5, 2015, and as high as 500 ppm over the water off the coast of coast of New Jersey on November 2, 2015. 

Emissions contribute to warmer waters - click to enlarge

The top panel of the image on the right shows that on December 11, 2015, carbon dioxide levels were as high as 474 ppm (parts per million, surface concentration) at the location marked by the green circle in New York.

The bottom panel of the image on the right shows that the water off the coast was warmer by as much as 10.3°C or 18.5°F at the location marked by the green circle on December 11, 2015.

The NASA video below shows carbon dioxide emissions over the year 2006.

It's not just CO2 off the North American coast that contributes to further warming of the Gulf Stream, many other emissions do so, including methane, CO, etc. Carbon monoxide (CO) is not a greenhouse gas, but it depletes hydroxyl, thus preventing oxidation of methane, a very potent greenhouse gas. The animation below shows a carbon monoxide level at green circle of 528 ppb on December 28, 2015, 0900z, while the sea surface temperature anomaly there was 15.8°F or 8.8°C on that day. 

Carbon monoxide reached much higher levels recently over land, as illustrated by the image below that shows a CO level of 2077 ppb in New York on January 6, 2016. 

These emissions heat up the Gulf Stream and make that ever warmer water is carried underneath the sea surface all the way into the Arctic Ocean, while little heat transfer occurs from ocean to atmosphere, due to the cold freshwater lid on the North Atlantic.

feedback #28 at the feedback page

The image on the right shows that it was warmer by as much as 9.6°C or 17.2°F near Svalbard on December 25, 2015, at the location marked by the green circle. The same anomalies were recorded on December 26, 2015, when the temperature of the water there was 11°C or 51.9 °F.

This gives an indication of how warm the water is that is being pushed underneath the sea surface into the Arctic Ocean.

Strong winds and high waves can cause more sea ice to be pushed along the edges of Greenland out of the Arctic Ocean, into the Atlantic ocean, expanding the cold freshwater lid on the North Atlantic, in a self-reinforcing feedback loop.

The image below shows the impact of these storms on sea ice speed and drift on December 31, 2015 (left) and a forecast for January 8, 2016 (right).

The danger is that, as warmer water reaches the seafloor of the Arctic Ocean, it will increasingly destabilize sediments that can contain huge amounts of methane in the form of free gas and hydrates.

Methane levels over the Arctic Ocean are already very high. Above image shows methane levels as high as 2745 ppb over the Arctic Ocean on January 2, 2016. High releases from the Arctic Ocean seafloor are pushing up methane levels higher in the atmosphere, as discussed in earlier posts such as this one.

So, while the extreme weather events that have occurred in the year 2015 are frightening, even more terrifying is the way the water of the Arctic Ocean is warming up. Sadly, this is rarely even discussed in the media. So, let's once more add the image below that should have been given more media attention.

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