Showing posts with label dangerous. Show all posts
Showing posts with label dangerous. Show all posts

Monday, June 20, 2022

Arctic sea ice June 2022 - why the situation is so dangerous

Sea Ice Extent


Arctic sea ice extent has fallen strongly in June 2022. On June 22, 2022, Arctic sea ice extent was among the lowest on record for the time of year, as illustrated by the above image, adapted from the National Snow and Ice Data Center (NSIDC Chartic). 

The image below, from an animation by Zachary Labe, shows Arctic sea ice extent up to June 20, 2022, based on Vishop data. The yellow line is the year 2022. The white line shows extent for the year 2012, when it reached a record minimum in September. The blue line shows extent the year 2020, when the minimum in September was second lowest.
 

The image below, adapted from Vishop, shows that on June 23, 2022, global sea ice extent was at a record low for the time of year.


La Niña

[ adapted from NOAA - click on images to enlarge ]
The fact that sea ice is so low for the time of the year is the more striking as we are currently in the depths of a persistent La Niña, which suppresses the temperature rise.

El Niños typically occur every 3 to 5 years, according to NOAA and as also illustrated by the NOAA image below, so the upcoming El Niño can be expected to occur soon.

The NOAA image below indicates that going from the bottom of a La Niña to the peak of an El Niño could make a difference of more than half a degree Celsius (0.5°C or 0.9°F).


Furthermore, the rise in sunspots from May 2020 to July 2025 could make a difference of some 0.15°C (0.27°F). The next El Niño looks set to line up with a high peak in sunspots, in a cataclysmic alignment that could push up the temperature enough to cause dramatic sea ice loss in the Arctic, resulting in runaway temperature rise by 2026.

Multi-year Sea Ice

The NSIDC compilation below illustrates how much multi-year sea ice has already declined over the years. The top panel shows the age of Arctic sea ice for the March 12 to 18 period in (a) 1985 and (b) 2022. The oldest ice, greater than 4 years old, is in red. Plot (c) shows the timeseries from 1985 through 2022 of percent cover of the Arctic Ocean domain (inset, purple region) by different sea ice ages during the March 12 to 18 period.


Sea Ice Volume

On June 18, 2022, Arctic sea ice volume was among the lowest on record for the time of year, as illustrated by the image below, adapted from Polarportal.


A Blue Ocean Event occurs when virtually all sea ice disappears and the surface color changes from white (sea ice) to blue (ocean). According to many, a Blue Ocean Event starts once Arctic sea ice extent falls below 1 million km².

The image on the right shows a trend pointing at zero Arctic sea ice volume by September 2027.

Note that the volume data in the image are averages for the month September ⁠— the minimum for each year is even lower. Furthermore, since zero volume implies zero extent, this indicates that a Blue Ocean Event (extent below 1 million km²) could happen well before 2027.

Sea Ice Thickness

The Naval Research Laboratory one-month animation below shows Arctic sea ice thickness up to June 18, 2022, with 8 days of forecasts added.


The above animation shows a dramatic fall in sea ice thickness over a large area, while sea ice is disappearing altogether in some places. This fall in thickness is mostly due to warm water from the Atlantic Ocean that is melting the sea ice hanging underneath the surface. This is where the sea ice constitutes the latent heat buffer, consuming incoming heat in the process of melting.

The University of Bremen combination image below shows the difference in sea ice thickness between June 1 and June 30, 2022. The image on the right shows a large areas where sea ice is less than 20 cm thick.


The NASA Worldview image below shows the situation on June 24, 2022. Plenty of water is showing up as close as 200 km to the North Pole.


Also view the NASA Worldview animation comparing sea ice at June 24 and 25, 2022 at facebook

Ocean Heat and decline of the Latent Heat Buffer


Ocean heat keeps rising; in 2021, despite La Niña conditions, ocean heat reached yet another record high, as illustrated by the above image, from an earlier post.

A 2019 analysis concludes that the latent heat tipping point gets crossed when the sea surface temperature anomaly on the Northern Hemisphere gets higher than 1°C above 20th century's temperature and when there is little or no thick sea ice left. As the image below indicates, the temperature anomaly of 1°C above the 20th century average looks set to be crossed in the course of the year 2021.


Close to the coast of Siberia, where much of the sea ice has disappeared altogether, the decline is due for a large part to warm water from rivers flowing into the Arctic Ocean. 


Sea ice has also disappeared altogether in the Bering Strait, for a great part due to warm water from rivers in Alaska, especially the Yukon River, the Kuskokwim River and the Copper River, as illustrated by the above NOAA image, which shows sea surface temperatures as high as 15.6°C or 60.08°F.


On June 10, 2022, the sea surface temperature anomaly from 1981-2011 in the Bering Strait was as high as 15.5°C or 27.9°F (at green circle), illustrated by the above nullschool.net image. In 1981-2011, the Bering Strait was still largely frozen at this time of year.

The NOAA image below illustrates how the Gulf Stream is pushing warm water toward the Arctic, with sea surface temperatures in the North Atlantic reaching as high as 32.1°C or 89.78°F on June 19, 2022. 


Latent heat is heat that is (less and less) going into melting the sea ice. The reason this heat is called latent (hidden) heat, is that it doesn't raise the temperature of the water, but instead gets consumed in the process of melting the ice. Latent heat is energy associated with a phase change, such as the energy consumed when solid ice turns into water (i.e. melting). During a phase change, the temperature remains constant. Sea ice acts as a buffer that absorbs heat, while keeping the temperature at zero degrees Celsius. As long as there is sea ice in the water, this sea ice will keep absorbing heat, so the temperature doesn't rise at the sea surface. The amount of energy absorbed by melting ice is as much as it takes to heat an equivalent mass of water from zero to 80°C.


The combination image below illustrates how much ocean heat is entering the Arctic Ocean from the Atlantic Ocean, heating up the sea ice from below.

The left panel shows the depth of the Arctic Ocean, with darker blue indicating greater depth.

In the right panel, the light blue, green and yellow colors indicate the thickest ice, located in the shallow waters off the coasts of North America and Greenland. The darker blue colors indicate where much of the sea ice has melted away, from below, as also illustrated by the one-month animation below showing sea ice thickness up to June 22, 2022, with an added 8 days of forecasts. The white color indicates where the sea ice has melted away entirely, e.g. in the Bering Strait and north of Siberia, mainly due to warm water from rivers entering the Arctic Ocean.


Once most of the sea ice that was hanging underneath the surface is gone, further heat will still keep moving underneath the sea ice from the Atlantic Ocean and - to a lesser extent - from the Atlantic Ocean into the Arctic Ocean. Without the latent heat buffer, this heat must go elsewhere, i.e. it will typically raise the temperature of the water. The atmosphere will also warm up faster. More evaporation will occur once the sea ice is gone, further warming up the atmosphere.

As the Latent Heat Tipping Point gets crossed, there may still be a thin layer of ice at the surface, at least as long as air temperatures are low enough to keep it frozen and as long as strong winds haven't pushed the sea ice out of the Arctic Ocean. This thin layer of ice will still consume some ocean heat below the surface, but at the same time it acts as a seal, preventing heat from the Arctic Ocean to enter the atmosphere. Even if a lot of sea ice remains, the situation is dangerous, if not even more dangerous. The continuing La Niña could cause a lot of thin sea ice to remain at the surface of the Arctic Ocean this year. The more sea ice remains, the less ocean heat can be transferred from the Arctic Ocean to the atmosphere over the Arctic Ocean, which means that more heat remains in the Arctic Ocean.

One huge danger is that, as the buffer disappears that until now has consumed huge amounts of ocean heat, more heat will reach methane hydrates at the seafloor of the Arctic Ocean, causing them to get destabilized and resulting in releases of methane from these hydrates and from free gas underneath that was previously sealed by the hydrates.

As the latent heat buffer of the sea ice underneath the surface disappears, more of this heat could then reach sediments at the seafloor of the Arctic Ocean, threatening eruptions to occur of seafloor methane (from hydrates and from free gas underneath the hydrates). The methane could similarly push up temperatures dramatically over the Arctic, and globally over the next few years. 

[ feedback #14: Latent Heat ]

The above 2014 image, from the feedbacks page, shows three of the numerous feedbacks that are accelerating warming in the Arctic. Feedback #1 is the albedo feedback. Feedback #14 refers to the loss of the Latent Heat Buffer and warming of the Arctic Ocean. Feedback #2 refers to methane releases. 

Heatwaves look set to continue on the Northern Hemisphere, extending heat over the Arctic Ocean and thus affecting Arctic sea ice from above, while warm water from rivers will cause more melting at the surface, and while rising ocean heat will continue to cause more melting of the ice underneath the surface. If this continues, we can expect a new record low for sea ice in September 2022 and the joint loss of the latent heat buffer and the loss of albedo could push up temperatures dramatically over the Arctic, while the additional methane could similarly push up temperatures dramatically over the Arctic, and globally over the next few years. 

[ The Buffer has gone, feedback #14 on the Feedbacks page ]

Conclusion

In conclusion, temperatures could rise strongly in the Arctic soon, due to sea ice loss in combination with an upcoming El Niño and a peak in sunspots, with the potential to drive humans extinct as early as in 2025, while temperatures would continue to skyrocket in 2026, making it in many respects rather futile to speculate about what will happen beyond 2026. At the same time, the right thing to do now is to help avoid the worst things from happening, through comprehensive and effective action as described in the Climate Plan.

• Blue Ocean Event 

• Polarportal

• Naval Research Laboratory

• University of Bremen

• NASA Worldview satellite

• NOAA - sea surface temperature
https://www.ospo.noaa.gov/Products/ocean/sst/contour/index.html

• nullschool
https://earth.nullschool.net

• Albedo, latent heat, insolation and more

• Latent Heat Buffer

• Feedbacks in the Arctic

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

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




Thursday, September 10, 2015

3.27°C warmer by 2030?

Will it be 3.27°C warmer by the year 2030?
In December 2015, world delegates will descend on Paris to ensure that global warming will not cross the guardrail of 2°C above pre-industrial levels.

[ click on images to enlarge them ]
In a way, we have already crossed this guardrail. NOAA data show that the year-to-date land surface temperature was 1.47°C above the 20th century average on the Northern Hemisphere in 2015, as illustrated by the image on the right.

Granted, there was less warming on the Southern Hemisphere, so the globally-averaged land surface temperature was a little bit lower, i.e. 1.34°C above the 20th century average. For reference, the image below on the right gives an overview of mean 1901-2000 temperatures. Anyway, the difference between hemispheres is small and not very relevant since most people live on the Northern Hemisphere.

[ click on image to enlarge ]
More importantly, this 1.47°C rise is a rise compared to the 20th century average. The 20th century average was some 0.60°C higher than temperatures were at the start of the NOAA record in 1880. In other words, temperatures for most people on Earth are already 2.07°C higher than they were in 1880.

Furthermore, between 1750 and 1880 the global average temperature had already increased by some 0.20°C.

Sure, 2015 is an El Niño year, but this El Niño is still strengthening, so 2016 could well be even warmer. Moreover, recent temperatures are in line with expectations of a polynomial trendline that is based on these NOAA data and that points at yet another degree Celsius rise by 2030, on top of the current level, as illustrated by the top image. Altogether, this would make it 3.27°C warmer than in 1750 for most people on Earth by the year 2030.

So, instead of acting as if dangerous global warming could possibly eventuate beyond the year 2100, delegates in Paris should commit to lowering temperatures, starting now.

To lower temperatures, cutting emissions alone will not be enough.

Stopping all emissions by people would make that the aerosols that are currently sent up in the air by burning fuel and that are currently masking the full impact of global warming, will fall out of the air in a matter of weeks. Until now, about half of the global temperature rise is suppressed by such aerosols. Stopping aerosols release overnight could make temperatures rise abruptly by 1.20°C in a matter of weeks.

Furthermore, carbon dioxide that is emitted now will take ten years to reach its peak impact, so we're still awaiting the full wrath of carbon dioxide emitted over the past decade.

A recent study calculates that global mean surface temperature may increase by 0.50°C after carbon emissions are stopped, and they will decrease only minimally from that level for the next 10,000 years.

Removing carbon dioxide from the atmosphere would not work fast enough to avoid further warming and acidification of the oceans. In fact, temperatures look set to rise even faster as feedbacks start to kick in more fully, such as albedo changes due to decline of the snow and ice cover in the Arctic and methane releases from the Arctic Ocean seafloor. Furthermore, water vapor will increase by 7% for every 1°C warming. Water vapor is one of the strongest greenhouse gases, so increasing water vapor will further contribute to a non-linear temperature rise.

In conclusion, the world needs to commit to comprehensive and effective action that includes both emission cuts and removal of greenhouse gases from the atmosphere and oceans, as well as further action to deal with the dire situation in the Arctic, as discussed at the Arctic-news Blog.




In December 2015, world delegates will descend on Paris to ensure that global warming will not cross the guardrail of 2°...
Posted by Sam Carana on Thursday, September 10, 2015

Monday, September 16, 2013

Is climate change already dangerous?

by David Spratt

Download PDF 
(23 pages)
In a compelling survey, this report answers the question many are afraid to ask: is climate change already dangerous?

This science survey measures the current manifestations and impacts of climate change against the "safe boundaries" metric; surveys the literature on tipping points and non-linear climate events; and provides a detail study of significant recent events in the Arctic.

Three big questions are asked and answered:
  • Is climate change dangerous for just the current increase in global temperature?
  • Is climate change dangerous for the further increases in temperature already implied by the current level of greenhouse gases?
  • By looking at events in climate history where greenhouse gas levels were similar to today, can further light be shone on the "already dangerous" question?
The answers are both shocking, and necessary, if climate policy-making is to escape the delusional paradigm within which it is stuck.

In a concluding section, this report argues that with clear evidence that climate change is already dangerous, we are in an emergency and face "…an unavoidably radical future". And we know from past experience that societies, once in emergency mode, are capable of facing up to and solving seemingly impossible problems.


This post was originally published at: