Arctic News

Saturday, March 18, 2017

Which Trend Is Best?

NASA just released temperature data for February 2017. Should we be worried? Yes, there are many reasons to be very worried.

Let's go back in time. This is from a post written ten years ago:
We may suddenly face a future in which many if not most people will have little or no access to food, water, medicines, electricity and shelter, while diseases go rampant and gangs and warlords loot and devastate the few livable areas left. Human beings as a species will face the risk of total extinction, particularly if many species of animals and plants that humans depend on will disappear. The post continues: Many people are still in denial about the severity of the problem of global warming, the accumulation of dangers and their progression.

Indeed, even today many people will still deny that such events could strike suddenly, e.g. within a few years time. Many people use linear trends to predict the future many years from now. As an example, the straight blue line on the graph below is a linear trend based on NASA 1880-current meteorological stations data. The problem is that linear trends, especially when based on data that go back many years, can make people overlook important recent changes such as the temperature rise that has taken place over the past few years, the decline of glaciers and sea ice and the recent increases in concentrations of carbon dioxide in the atmosphere.

[ click on image to enlarge ]

An alternative approach is to use recent data, e.g., from the year 2012, and then calculate a polynomial trend that extends a few years into the future. Taking such an approach can result in a polynomial trend (red curved line) that is contained in the NASA Land+Ocean data from January 2012 to February 2017. This trend shows the potential for a 10°C (18°F) rise four years from now, and this should act as a powerful warning.

The appropriateness of linear versus non-linear trends was also discussed earlier at the Controversy page.

In addition to looking at trends that are contained in such data, it makes sense to analyse the different elements contributing to such a rise. Such elements are discussed in more detail at the extinction page, which confirms the potential for a 10°C temperature rise within years, i.e. by the year 2026.

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

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

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

• Controversy
http://arctic-news.blogspot.com/p/controversy.html

• Warning of mass extinction of species, including humans, within one decade
http://arctic-news.blogspot.com/2017/02/warning-of-mass-extinction-of-species-including-humans-within-one-decade.html

Monday, March 13, 2017

Methane Erupting From Arctic Ocean Seafloor

Seafloor methane often missed in measurements

Large amounts of methane are erupting from the seafloor of the Arctic Ocean. These methane eruptions are often missed by measuring stations, because these stations are located on land, while measurements are typically taken at low altitude, thus missing the methane that rises in plumes from the Arctic Ocean. By the time the methane reaches the coast, it has typically risen to higher altitudes, thus not showing up in low-altitude measurements taken at stations on land.

The image below shows the highest mean global methane levels on March 10 over the years from 2013 through 2017, for selected altitudes corresponding to 945 mb (close to sea level) to 74 mb.

The table below shows the altitude equivalents in feet (ft), meter (m) and millibar (mb).

57,016 ft	44,690 ft	36,850 ft	30,570 ft	25,544 ft	19,820 ft	14,385 ft	8,368 ft	1,916 ft
17,378 m	13,621 m	11,232 m	9,318 m	7,786 m	6,041 m	4,384 m	2,551 m	584 m
74 mb	147 mb	218 mb	293 mb	367 mb	469 mb	586 mb	742 mb	945 mb

The signature of seafloor methane

Above image shows that, over the years, methane levels have risen strongly high in the Troposphere, up into the Stratosphere. This looks like the signature of methane that originated from the seafloor of the Arctic Ocean. The image below further explains why.

The Tropopause separates the Troposphere from the Stratosphere. The Troposphere ends at a height of some 9 km (5.6 mi; 30,000 ft) at the poles, and at a height of some 17 km (11 mi; 56,000 ft) at the Equator.

As said, methane is erupting from the seafloor of the Arctic Ocean concentrated in plumes, unlike methane from wetlands and agriculture that is typically emitted over a wide area. Since seafloor methane is rising in plumes, it hardly shows up on satellite images at lower altitude either, as the methane is very concentrated inside the area of the plume, while little or no increase in methane levels is taking place outside the plume. Since the plume will cover less than half the area of one pixel, such a plume doesn't show up well at low altitudes on satellite images,

Methane over the Arctic typically does show up on satellite images at altitudes between 4.4 km and 6 km (14,400 ft and 19,800 ft). Seafloor methane will show up better at these higher altitudes where it spreads out over larger areas. At even higher altitudes, methane will then follow the Tropopause, i.e. the methane will rise in altitude while moving closer to the equator.

NOAA image

In conclusion, methane originating from the seafloor of the Arctic Ocean can strongly contribute to high methane levels that show up over the Equator at higher altitudes, but this methane can be misinterpreted for methane originating from tropical wetlands.

Methane levels as high as 2846 ppb

[ click on images to enlarge ]

On March 14, 2017, methane levels were as high as 2846 ppb, as illustrated by the image on the right. While the origin of these high levels looks hard to determine from this image, the high levels showing up over the East Siberian Arctic Shelf (ESAS) later that day (image underneath) give an ominous warning that destabilization of methane hydrates is taking place.

The images also show that high methane levels are showing up at many other places, e.g. over Antarctica where hydrate destabilization also appears to be taking place, which could also be the cause of noctilucent clouds as discussed in earlier posts (see links at end of this post).

Why is methane erupting from the Arctic Ocean?

Why are increasingly large quantities of methane erupting from the seafloor of the Arctic Ocean? The main driver is warming of the Arctic Ocean that is destabilizing once-permanently-frozen sediments that contain huge amounts of methane in the form of hydrates and free gas.

Ocean heat is increasingly entering the Arctic Ocean from the Atlantic Ocean, as illustrated by the images below. Self-reinforcing feedbacks, in particular sea ice decline, further speed up warming of the Arctic Ocean.

[ from earlier post ]

Self-reinforcing feedback loops

[ click on images to enlarge ]

Meanwhile, the next El Niño event has already started, at a time when sea surface temperature anomalies over the Pacific Ocean are very high as illustrated by the image on the right showing sea surface temperature anomalies east of South America as high as 5.3°C or 9.5°F (compared to 1981-2011) on February 28, 2017.

Greater contrast between sea surface temperatures and temperatures on land has contributed to flooding in California and South America.

Importantly, more water vapor in the atmosphere results in more warming, since water vapor is a potent greenhouse gas.

[ click on images to enlarge ]

Above images shows ECMWF (European Centre for Medium-Range Weather Forecasts) plumes with strong positive anomalies in all three El Niño regions (on the right).

In other words, temperatures in 2017 look set to be very high, which spells bad news for the Arctic where temperature anomalies are already several times higher than in the rest of the world.

Arctic sea ice looks set to take a steep fall, as illustrated by the image below.

The danger is that further self-reinforcing feedback loops such as albedo decline and methane releases will accelerate warming and, in combination with further warming elements, cause a temperature rise as high as 10°C or 18°F by the year 2026, as 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

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

• Warning of mass extinction of species, including humans, within one decade
http://arctic-news.blogspot.com/2017/02/warning-of-mass-extinction-of-species-including-humans-within-one-decade.html

• Low sea ice extent contributes to high methane levels at both poles
http://arctic-news.blogspot.com/2017/03/low-sea-ice-extent-contributes-to-high-methane-levels-at-both-poles.html

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

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

Saturday, March 4, 2017

Low sea ice extent contributes to high methane levels at both poles

[ click on images to enlarge ]

On March 2, 2017, Antarctic sea ice extent was at a record low since satellite readings started.

As the image on the right shows, sea ice extent in 2017 (light blue) around Antarctica has been more than 1 million km² lower than the 1981-2010 median.

At the same time, Arctic sea ice extent was at a record low for the time of the year since 1979.

As the image underneath on the right shows, Arctic sea ice extent in 2017 has also been more than than 1 million km² lower than the 1981-2010 median.

[ click on images to enlarge ]

For about half a year now, global sea ice extent has been more than 2 million km² lower than it used to be, not too long ago, as illustrated by the image below, by Wipneus.

This means that a lot of sunlight that was previously reflected back into space, has been absorbed instead by Earth, contributing to global warming, especially at the poles.

Greater warming at the poles has also caused more extreme weather, resulting in stronger winds and waves and in wild weather swings, further accelerating the decline of the sea ice.

The combination of rising ocean heat and stronger winds looks set to devastate the sea ice around Antarctica. Ocean heat is increasing particularly in the top layer (see image on the right).

Warming water is increasingly reaching the coast of Antarctica. The image below illustrates how much sea ice melt has occurred close to the coast of Antarctic over the past few months, while much sea ice has drifted away from the coast due to strong currents and wind.

As said, less sea ice means that a lot of sunlight is no longer reflected back into space, but is instead further warming up the poles. As a result, methane levels can be very high at both poles. The combination image below shows methane levels as high as 2560 ppb on March 1, 2017. The image in the panel on the left shows high methane levels over Antarctica in an area with much grey, indicating that it was hard to get a good reading there. On the image in the panel on the right, high methane levels do show up clearly in that area.

[ click on images to enlarge ]

As discussed before, methane hydrates can be present both on Greenland and on Antarctica underneath thick layers of snow and ice. Due to global warming, wild weather swings are now common at the poles, as illustrated by the image below. This can cause sequences of rapid and extreme expansion, compacting and fracturing of snow and ice, resulting in destabilization of methane hydrates contained in the permafrost.

The image below shows methane levels as high as 2562 ppb, with solid magenta-colored areas showing up over the Laptev Sea on March 4, 2017.

The image below shows that sea surface temperatures in the Arctic Ocean were as high as 12.7°C or 54.9°F on March 3, 2017 (at the location marked by the green circle), i.e. 12°C or 21.6°F warmer than in 1981-2011.

Below is the same image, but in a different projection and showing sea surface temperatures, rather than anomalies. In 1981-2011, the temperature of the water at a spot near Svalbard (green circle) was 0.7°C (33.3°F.). On March 3, 2017, it was 12°C (21.6°F) warmer on that spot.

The danger is that self-reinforcing feedback loops such as albedo decline and methane releases will further accelerate warming and will, in combination with further warming elements, cause a temperature rise as high as 10°C or 18°F by the year 2026, as 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

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

• Methane hydrates
http://methane-hydrates.blogspot.com/2013/04/methane-hydrates.html

• Earthquakes in the Arctic Ocean
http://arctic-news.blogspot.com/2014/04/earthquakes-in-the-arctic-ocean.html

Saturday, February 25, 2017

Accelerating growth in CO₂ levels in the atmosphere

CO₂ Growth

In 2016, CO₂ levels in the atmosphere grew by 3.36 ppm (parts per million), a new record since 1959 and much higher than the previous record set in 2015.

Worryingly, above graph has a trendline added pointing at a growth rate in CO₂ levels of 6 ppm per year by 2026.

Growth in levels of CO₂ in the atmosphere is accelerating, despite reports that - for the third year in a row - carbon dioxide emissions from fossil fuels and industry (including cement production) had barely grown, as illustrated by the Global Carbon Project image below.

Why is growth in CO₂ levels in the atmosphere accelerating?

So, what makes growth in CO₂ levels in the atmosphere accelerate? As discussed in a previous post, growth in CO₂ levels in the atmosphere is accelerating due to:

Deforestation and Soil Degradation:
Agricultural practices such as depleting groundwater and aquifers, plowing, mono-cultures and cutting and burning of trees to raise livestock can significantly reduce the carbon content of soils, along with soil moisture and nutrients levels.
Climate change and extreme weather events:
The recent jump in global temperature appears to have severely damaged soils and vegetation. Soil carbon loss and enhanced decomposition of vegetation appear to have occurred both because of the temperature rise and the resulting extreme weather events such as heatwaves, drought, dust-storms and wildfires, and storms, hail, lightning, flooding and the associated erosion, turning parts of what was once a huge land sink into sources of CO₂ emissions.
Moreover, extreme weather events can also lead to emissions other than CO₂ emissions, such as soot, nitrous oxide, methane and carbon monoxide, which can in turn cause a rise in the levels of ground-level ozone, thus further weakening vegetation and making plants even more vulnerable to pests and infestations.
Oceans may also be taking up less CO₂ than before:
Oceans have absorbed some 40% of CO₂ emissions since the start of the industrial era. Up until recently, oceans still took up some 26% of carbon dioxide emitted by people annually. As discussed earlier, oceans are getting warmer, and warm water holds less oxygen than cold water. Furthermore, as the water warms, it tends to form a layer at the surface that does not mix well with cooler, nutrient-rich water below, depriving phytoplankton of some of the nutrients needed in order for phytoplankton to grow. Less phytoplankton in the oceans means that oceans become less able to take up carbon dioxide from the atmosphere. A study by Boyce et al. found a decrease of about 1% per year of phytoplankton in oceans globally. Sergei Petrovskii, co-author of a 2015 study, found that a rise in the water temperature of the world’s oceans of about 6°C could stop oxygen production by phytoplankton by disrupting the process of photosynthesis, adding that “About two-thirds of the planet’s total atmospheric oxygen is produced by ocean phytoplankton – and therefore cessation would result in the depletion of atmospheric oxygen on a global scale. This would likely result in the mass mortality of animals and humans.”

Biomass

Sensitivity

Meanwhile, research including a 2014 study by Franks et al. concludes that the IPCC was too low in its estimates for the upcoming temperature rise locked in for current CO₂ levels. A study by Friedrich et al. updates IPCC estimates for sensitivity to CO₂ rise, concluding that temperatures could rise by as much as 7.36°C by 2100 as a result of rising CO₂ levels.

When also taking further elements than CO₂ more fully into account, we could face an even larger temperature rise, i.e. a rise of 10°C (or 18°F) by 2026 (compared to pre-industrial), as further described at the extinction page that specifies the different elements of such a rise, including a 0.5°C rise due to CO₂ emissions from 2016 to 2026. The CO₂ growth discussed in this post appears to be in line with such a rise and in line with the associated loss of carbon sinks and rising vulnerability of carbon pools.

The situation looks particularly threatening in the Arctic where many of the most vulnerable carbon pools are located, where temperatures are rising fastest and where CO₂ levels have recently risen rapidly (see image below with CO₂ readings at Barrow, Alaska).