Arctic News: aerosols

Showing posts with label aerosols. Show all posts

Friday, March 13, 2020

2°C crossed

It's time to stop denying how precarious the situation is.

Remember the Paris Agreement? In 2015, politicians pledged to hold the global temperature rise to well below 2°C above pre-industrial levels and pledged they would try and limit the temperature rise to 1.5°C above pre-industrial levels. Well, an analysis by Sam Carana shows that it was already more than 1.5°C above pre-industrial when the Paris Agreement was reached.

View details of Sam Carana's analysis

In Sam Carana's analysis, the year 1750 is used as the baseline for pre-industrial. The analysis shows that we meanwhile have also crossed the 2°C threshold (in February 2020) and that the temperature rise looks set to rapidly drive humans and eventually most if not all species on Earth into extinction.

Yet, our politicians refuse to act!

Accelerating temperature rise

Indeed, there are indications that the recent rise is part of a trend that points at even higher temperatures in the near future, as also discussed at this analysis page. Polynomial trends can highlight such acceleration better than linear trends. The 1970-2030 polynomial trend in the image below is calculated over the period from 1880 through to February 2020. The trend points at 3°C getting crossed in 2026.

In above image, the January 2020 and February 2020 anomalies are above the trend. This indicates that the situation might be even worse.

A polynomial trend calculated over a shorter period can highlight short-term variation such as associated with El Niño events and can highlight feedbacks that might otherwise be overlooked. The 2010-2022 trend in the image below is calculated with 2009-Feb.2020 data. The trend indicates that 2°C was crossed in February 2020, and looks set to keep rising and cross 3°C in 2021, more specifically in January next year, which is less than a year away.

Such a steep rise is in line with unfolding developments that are causing the aerosol masking effect to fall away, such as a decrease in industrial activity due to COVID-19 fears. The image below shows a potential rise of 18°C or 32.4°F from 1750 by the year 2026.

Above image was posted more than a year ago and illustrates that much of this potentially huge temperature rise over the next few years could eventuate as a result of a reduction in the cooling now provided by sulfates. In other words, a steep temperature rise could result from a decline in industrial activity that is caused by fears about the spread of a contagious virus, as also discussed in the video at an earlier post.

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

Links

• Analysis: Crossing the Paris Agreement thresholds
https://arctic-news.blogspot.com/p/crossing.html

• A rise of 18°C or 32.4°F by 2026?
https://arctic-news.blogspot.com/2019/02/a-rise-of-18c-or-324f-by-2026.html

• How much warming have humans caused?
https://arctic-news.blogspot.com/2016/05/how-much-warming-have-humans-caused.html

• Arctic Ocean January 2020
https://arctic-news.blogspot.com/2020/02/arctic-ocean-february-2020.html

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

In the video below, Guy McPherson discusses the situation.

Thursday, July 13, 2017

Wildfires

Levels of carbon dioxide (CO2) in the atmosphere are accelerating, even though emissions from fossil fuel burning have remained virtually the same over the past few years.

One of the reason behind this is accelerating emissions from wildfires as temperatures are rising.

Wildfires in Nevada caused CO2 to reach levels as high as 742 ppm on July 12, 2017 (green circle image on the right).

Global warming is greatly increasing the chance for what was previously seen as an extreme weather event to occur, such as a combination of droughts and storms. Heat waves and droughts can cause much vegetation to be in a bad condition, while high temperatures can come with strong winds, storms and lightning.

Wildfires cause a range of emissions, including CO2, soot, methane and carbon monoxide (CO). In Nevada, CO levels were as high as 30.43 ppm (green circle image right).

Above satellite image below shows the smoke plumes and the charred area. The google maps image below further shows where the fires were burning.

At the moment, wildfires are hitting many places around the world.

Wildfires caused carbon dioxide to reach levels as high as 746 ppm in Kazakhstan on July 11, 2017 (green circle on image on the right).

Carbon monoxide levels in the area were as high as 20.96 ppm on July 10, 2017.

The satellite image shows wildfires in Kazakhstan on July 9, 2017.

The satellite images show wildfires in Kazakhstan on July 11, 2017.

On July 16, 2017, CO₂ reached levels as high as 830 ppm in North America at the location marked by the green circle on the image below. Note that fires are burning at multiple locations.

The image below shows the location (red marker) where the fires burned in Canada.

That same day, July 16, 2017, CO₂ reached levels as high as 873 ppm in Mongolia, as shown by the image on the right.

The image also shows further fires burning in Siberia.

Carbon monoxide levels were as high as 37.19 ppm where the fires burned in Mongolia on July 16, 2017, as shown by the image below.

The image below shows the location (red marker) where the fires burned in Mongolia. The image also shows Lake Baikal across the border with Russia.

On July 22, 2017, CO₂ reached levels as high as 1229 ppm in Montana, while CO levels at the time were as high as 56.38 ppm at that location (green circle on image below).

The satellite image below shows the situation in Montana on the next day, July 23, 2017. See also the
NASA post Grassland Fires Tear Through Montana.

Furthermore, on July 23, 2017, CO₂ reached levels as high as 884 ppm at another (nearby) location in Montana (green circle on image below).

Meanwhile, temperatures keep rising. Surface temperature as high as 53.1°C or 127.5°F were forecast in Iran for July 11, 2017, at the location marked by the green circle on the image below.

At 1000 mb (image below), temperatures in Iran were forecast to be slightly lower, i.e. as high as 51.9°C or 125.3°F at the location marked by the at green circle, but note the difference in color, especially over Greenland, the Himalayas and the Tibetan Plateau.

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

Aerosols

Some aerosols, particularly sulfur dioxide, have a cooling effect, making that they partly mask the warming effect of other emissions by people. The IPCC AR4 image below shows that the direct and cloud albedo effect of aerosols equals a radiative forcing of as much as -2.7 W/m². In other words, if this masking effect were to fall away, warming would increase by as much as 2.7 W/m², according to IPCC AR4 figures.

Anthropogenic aerosols are also suppressing the Pacific Decadal Oscillation, making that less heat gets transferred from oceans to the atmosphere. Recent research concludes that future reduction of anthropogenic aerosol emissions, particularly from China, would promote positive Pacific Decadal Oscillation, thus further speeding up warming over the coming years.

Dimethyl sulphide emissions from oceans constitute the largest natural source of atmospheric sulphur, and such emissions can decrease with ongoing ocean acidification and climate change. This could particularly impact specific regions such as Antarctica, speeding up warming and loss of sea ice there, as discussed at this paper.

The net warming effect of open biomass burning was estimated in a 2014 study by Mark Jacobson to amount to 0.4 W/m² of radiative forcing. Imagine a scenario in which many people stopped burning fossil fuels for heating, cooking and energy. That would be great, but if many of them instead switched to burning biomass in woodburners and open fires, while wildfires increased strongly, the net warming from associated aerosols would increase dramatically.

A recent paper by James Hansen uses equilibrium fast-feedback climate sensitivity of ¾°C per W/m², while another recent paper suggest that the temperature rise per W/m² could be even stronger.

A high-end increase in net radiative forcing combined with a strong temperature rise per W/m² could cause a temperature rise as a result of changes in aerosols of as much as 2.5°C in a matter of years, as suggested in earlier posts such as this one.

Friday, July 15, 2016

A Global Temperature Rise Of More than Ten Degrees Celsius By 2026?

How much have temperatures risen and how much additional warming could eventuate over the next decade? The image on the right shows a potential global temperature rise by 2026 from pre-industrial levels. This rise contains a number of elements, as discussed below from the top down.

February 2016 rise from 1900 (1.62°C)

The magenta element at the top reflects the temperature rise since 1900. In February 2016, it was 1.62°C warmer compared to the year 1900, so that's a rise that has already manifested itself.

Rise from pre-industrial levels to 1900 (0.3°C)

Additional warming was caused by humans before 1900. Accordingly, the next (light blue) element from the top down uses 0.3°C warming to reflect anthropogenic warming from pre-industrial levels to the year 1900.

When also taking this warming into account, then it was 1.92°C (3.46°F) warmer in February 2016 than in pre-industrial times, as is also illustrated on the image below.

Warming from the other elements (described below) comes on top of the warming that was already achieved in February 2016.

Rise due to carbon dioxide from 2016 to 2026 (0.5°C)

The purple element reflects warming due to the amount of carbon dioxide in the atmosphere by 2026. While the IEA reported that energy-related carbon dioxide emissions had not risen over the past few years, carbon dioxide levels in the atmosphere have continued to rise, due to feedbacks that are kicking in, such as wildfires and reduced carbon sinks. Furthermore, maximum warming occurs about one decade after a carbon dioxide emission, so the full warming wrath of the carbon dioxide emissions over the past ten years is still to come. In conclusion, an extra 0.5°C warming by 2026 seems possible as long as carbon dioxide levels in the atmosphere and oceans remain high and as temperatures keep rising.

Removal of aerosols masking effect (2.5°C)

With 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. While on the one hand not all of the aerosols masking effect may be removed over the next ten years, there now are a lot more aerosols than in 2010. A 2.5°C warming due to removal of part of the aerosols masking effect therefore seems well possible by the year 2026.

Albedo changes in the Arctic (1.6°C)

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, calculated Professor Peter Wadhams in 2012. A 1.6°C warming due to albedo changes (i.e. decline of both Arctic sea ice and snow and ice cover on land) therefore seems well possible by the year 2026.

Methane eruptions from the seafloor (1.1°C)

". . 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. Note that 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. Professor Peter Wadhams co-authored a study that calculated that methane release from the seafloor of the Arctic Ocean could yield 0.6°C warming of the planet in 5 years (see video at earlier post). In conclusion, as temperatures keep rising, a 1.1°C warming due to methane releases from clathrates at the seafloor of the world's oceans seems well possible by the year 2026.

Extra water vapor feedback (2.1°C)

Rising temperatures will result in more water vapor in the atmosphere (7% more water vapor for every 1°C warming), further amplifying warming, since water vapor is a potent greenhouse gas. Extra water vapor will result from warming due to the above-mentioned albedo changes in the Arctic and methane releases from the seafloor that could strike within years and could result in huge warming in addition to the warming that is already there now. As the IPCC says: "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. Given a possible additional warming of 2.7°C due to just two elements, i.e. Arctic albedo changes and seafloor methane, an additional warming over the next decade of 2.1°C due to extra water vapor in the atmosphere therefore does seem well possible by the year 2026.

Further feedbacks (0.3°C)

Further feedbacks will result from interactions between the above elements. Additional water vapor in the atmosphere and extra energy trapped in the atmosphere will result in more intense storms and precipitation, flooding and lightning. Flooding can cause rapid decomposition of vegetation, resulting in strong methane releases. Furthermore, plumes above the anvils of severe storms can bring water vapor up into the stratosphere, contributing to the formation of cirrus clouds that trap a lot of heat that would otherwise be radiated away, from Earth into space. The number of lightning strikes can be expected to increase by about 12% for every 1°C of rise in global average air temperature. At 3-8 miles height, during the summer months, lightning activity increases NOx by as much as 90% and ozone by more than 30%. The combination of higher temperatures and more lightning will also cause more wildfires, resulting in emissions such as of methane and carbon monoxide. Ozone acts as a direct greenhouse gas, while ozone and carbon monoxide can both act to extend the lifetime of methane. Such feedbacks may well result in an additional 0.3°C warming by the year 2026.

Total potential global temperature rise by 2026 (10°C or 18°F)

Adding up all the warming associated with the above elements results in a total potential global temperature rise (land and ocean) of more than than 10°C or 18°F within a decade, i.e. by 2026. As said before, this scenario assumes that no geoengineering will take place over the next decade.

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

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 feet	44690 feet	36850 feet	30570 feet	25544 feet	19820 feet	14385 feet	8368 feet	1916 feet
17378 m	13621 m	11232 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.