Arctic News: ocean heat

Showing posts with label ocean heat. Show all posts

Saturday, March 2, 2024

Arctic sea ice set for steep decline

The February 2024 temperature (at 2 meter) was much higher than in 1951-1980, especially in the Arctic, as the above image shows.

The above image is adapted from NASA and shows an average February 2024 temperature anomaly of 1.44°C above 1951-1980, with anomalies showing up as high as 11°C.

The above image is created with NASA Land+Ocean monthly mean global temperature anomalies versus a 1900-1923 custom base, further adjusted by 0.99°C to reflect ocean air temperatures, higher polar anomalies and a pre-industrial base.

Two trends are added, the blue trend is based on all data (Jan.1880-Feb.2024) and the magenta trend is based on a shorter period (Jan.2010-Feb.2024), to better reflect variables such as El Niño and non-linear feedbacks as discussed in the page Feedbacks in the Arctic and in this recent post.

Ocean temperature

Sea surface temperatures (60°S-60°N, 0-360°E) reached a new record high of 21.22°C on March 10, 2024, in the Climate Reanalyzer daily records that go back to 1981.

Sea surface temperatures may get even higher later this year. What could make the sea surface temperature go up even higher?

[ click on images to enlarge ]

The highest daily sea surface temperatures for the year are typically reached in March.

This was the case for the previous years on record going back to 1981, except for the year 2023 when the current El Niño started to emerge, resulting in the highest peak for the year occurring in August 2023.

There is a 100% probability that El Niño will be present during the 3 months from February 2024 to April 2024, according to NOAA predictions updated February 26, 2024.

The image below shows the Northern Hemisphere Sea Surface Temperature Anomaly, January 2000-February 2024 NOAA data (degrees Celsius).

After an astonishing rise in 2023, sea surface temperatures have come down only a little bit in Winter on the Northern Hemisphere, raising the potential for a huge rise in ocean heat later in 2024 that threatens to destabilize sediments at the seafloor of the Arctic Ocean and cause huge amounts of methane to erupt and abruptly enter the atmosphere.

[ click on images to enlarge ]

Ocean heat content keeps rising at a rate of change that is non-linear, as illustrated by the image below, by Zack Labe.

North Atlantic

The animation below, from Nahel Belgherze, illustrates how much hotter the North Atlantic has been over the past 365 days, while a big rise in temperature can be expected over the next few months, due to the change in season.

In February 2024, the temperature (at 2 meter) over the North Atlantic was 1.927°C higher than 1951-1980, as illustrated by the image below.

The map below shows the North Atlantic sea surface temperature anomaly versus 1951-1980 in February 2024.

Arctic surface air temperature

The surface air temperature in the Arctic (66.5-90°N, 0-360°E) was 5.2°C above 1979-2000 on March 3, 2024, the highest anomaly on record for the time of year, as illustrated by the image below.

[ click on images to enlarge ]

Arctic sea ice

As the atmosphere and the oceans keep heating up, Arctic sea ice keeps declining. As illustrated by the image below, Arctic sea ice extent was 14.746 million km² on March 6, 2024.

As the above image shows, there are a few years with lower sea ice extent during this time of year than in 2024, which could be due to more water vapor in the air causing more precipitation in the Arctic. At this time of year, Arctic sea ice has typically reached its maximum annual extent and goes into steep descend until half September. With the change in seasons, more sunlight will be reaching the Northern Hemisphere and Arctic sea ice looks set for a steep decline over the next few months.

As illustrated by the above image, Arctic sea ice volume is already at a record low for the time of year, at a time when little or no sunlight is yet reaching the Arctic. Given that Arctic sea ice currently is not at a record low extent for the time of year, this indicates that the sea ice is very thin, due to ocean heat causing sea ice to melt from below. Moreover, as illustrated by the map below, much of the thicker sea ice is located off the east coast of Greenland. This sea ice and the purple-colored sea ice can be expected to melt away quickly with the upcoming rise in temperatures over the next few months, as also discussed in earlier posts such as this one.

Emissions and concentrations of greenhouse gases keep rising

Meanwhile, emissions keep rising. The image below, adapted from IEA, shows the increase in energy-related carbon dioxide emissions, 1900-2023.

February 2024 CO₂ was about 425 ppm (background image below). February 2023 CO₂ was 420.3 ppm (inset right). The highest annual rise on record is about 3 ppm, reached in 1998 and in 2015/2016 (inset left).

The threat

The threat of a huge, abrupt temperature rise has been described many times before, e.g. on the Threat page that describes many elements contributing to the threat, both cumulatively and interactively, with some of the content dating back as far as 2007. Another page with more background is the Extinction page.

Further illustrating the threat is the image below, adapted from Climate Reanalyzer and using a CMIP6 SSP585 model. The image shows what the temperature anomaly (at 2 meter and compared to 1851-1900) could be by 2100. Such a temperature rise may unfold much earlier when including numerous feedbacks kicking in strongly.

What can strongly contribute to such a rise is that, without the buffer constituted by thicker sea ice, an influx of ocean heat threatens to destabilize hydrates contained in sediments at the seafloor of the Arctic Ocean, resulting in eruptions of huge amounts of methane.

[ The buffer is gone - Latent Heat Tipping Point crossed ]

Climate Emergency Declaration

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.

Links

• Climate Reanalyzer - daily sea surface temperature (60°S-60°N, 0-360°E)
https://climatereanalyzer.org/clim/sst_daily

• NASA - Temperature Analysis
https://data.giss.nasa.gov/gistemp

• NOAA - ENSO: Recent Evolution, Current Status and Predictions (February 26, 2024 update)
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

• Ocean heat content - image by Zack Labe

https://zacklabe.com/climate-change-indicators

• North Atlantic daily sea surface temperature - animation by Nahel Belgherze
https://twitter.com/WxNB_/status/1765065264109101393

• Danish Meteorological Institute - Arctic sea ice volume and thickness
https://ocean.dmi.dk/arctic/icethickness/thk.uk.php

• International Energy Agency (IEA) - CO2 Emissions in 2023 report

https://www.iea.org/reports/co2-emissions-in-2023

• Keeling Curve, Scripps Institution of Oceanography, UC San Diego - CO₂ at Mauna Loa, Hawaii

https://keelingcurve.ucsd.edu

• NOOA - Monthly Averages CO₂ at Mauna Loa, Hawaii

https://gml.noaa.gov/ccgg/trends/graph.html

• NOAA - annual increase of CO₂ at Mauna Loa, Hawaii
https://gml.noaa.gov/ccgg/trends/gr.html

• Feedbacks in the Arctic

https://arctic-news.blogspot.com/p/feedbacks.html

• The Threat

https://arctic-news.blogspot.com/p/threat.html

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

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

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

Friday, January 19, 2024

Potential temperature trends

[ click on images to enlarge ]

The above image shows potential temperature trends. Four of the trends are global ones and one trend is based on Arctic (64°North-90°North) data:

The red line is a polynomial trend based on 15 years of Arctic data (2009-2023).
The green line is a linear trend based on 1880-2023 global data.
The yellow line is a linear trend based on 2009-2023 global data.
The light blue line is a 10-year moving average (trailing), based on global data.
The dark blue line is a polynomial trend, based on 2015-2023 global data, showing global temperatures catching up with the Arctic rise in temperature.

Note that the above image uses annual anomalies from 1951-1980. Recent posts show that, when adjustments are made for an earlier base, for ocean air temperatures and for higher polar anomalies, the 2023 anomaly could be as high as 2.5°C from pre-industrial and when using monthly data, the anomaly could be as high as 2.73°C from pre-industrial.

Temperature rise hits Arctic most strongly

Due to feedbacks such as sea ice loss, the temperature rise is felt most strongly at higher latitudes North, as illustrated by the three images below, again using a 1951-1980 baseline.

The image below shows the December 2023 temperature anomaly.

The image below shows the 2023 temperature anomaly.

The image below shows how the temperature rise has unfolded from 2000.

[ Arctic Ocean hit most strongly by temperature rise ]

Over the next few years, the temperature rise in the Arctic could accelerate even more strongly as a result of crossing of two tipping points, i.e. the Latent Heat Tipping Point and the Seafloor Methane Tipping Point, as illustrated by the image below, from an earlier post.

[ increasing ocean heat ]

Note again that annual data are used in the above image. An earlier analysis using monthly data shows that the seafloor methane tipping point was reached in August 2023.

Arctic sea ice extent

Arctic sea ice extent in 2024 was larger than many expected. One of the reasons for this is that Greenland ice has been melting faster than previously thought, as pointed out by a recent study that also includes retreat of glaciers that already lie mostly below sea level. More melting of ice on Greenland has resulted in a larger south-bound flow of icebergs and meltwater, contributing to cooling of the North Atlantic sea surface and slowing down of the Atlantic meridional overturning circulation (AMOC), and in turn contributing to suppress temperatures in the Arctic. As a result, loss of Arctic sea ice extent has been less than would otherwise have been the case. Yet, the temperature rise may soon overwhelm this suppression.

Cold freshwater lid at surface of North Atlantic

[ ocean stratification, from earlier post ]

Slowing down of AMOC and cooling due to heavier melting of Greenland's ice is causing less ocean heat to reach the Arctic Ocean, while a huge amount of ocean heat is accumulating in the North Atlantic, as it did in 2023. A large part of this heat in the North Atlantic can also be present underneath the sea surface.

These developments occur at the same time as ocean stratification increases (see above image) as temperatures rise, as more freshwater enters the ocean as a result of more meltwater and of runoff from land and from rivers, and as more evaporation takes place and more rain falls further down the path of the Gulf Stream, all of which can contribute to formation and growth of a cold, freshwater lid at the surface of the North Atlantic.

[ cold freshwater lid on North Atlantic ]

Furthermore, storms can get stronger as temperatures rise and as changes take place to the Jet Stream. Strong wind can temporarily speed up currents that carry huge amounts of ocean heat with them toward the Arctic Ocean, as discussed in earlier posts such as this one. Much of the ocean heat in the North Atlantic can therefore be pushed abruptly underneath this freshwater lid and flow into the Arctic Ocean.

The danger is that huge amounts of ocean heat can abruptly get pushed into the Arctic Ocean and that the influx of ocean heat will destabilize hydrates contained in sediments at the seafloor of the Arctic Ocean, resulting in eruptions of huge amounts of methane.

[ click on images to enlarge ]

This danger is further illustrated by the above compilation image, showing forecasts for January 27, 2024 of:
(1) surface wind and temperature (-3.6°C or 25.4°F at the North Pole)
(2) surface wind
(3) wind at 700 hPa
(4) wind at 250 hPa (Jet Stream) and
(5) ocean currents at surface and wave height.

The image below shows that temperatures are forecast to be above freezing near the North Pole on January 26, 2024 20:00 UTC (downloaded January 26, 2024 06:00 UTC).

Ominously, the North Atlantic sea surface was much hotter in early 2024 than it was in early 2023.

And ominously, the daily sea surface temperature reached a record high on January 31, 2024, when the daily sea surface temperature reached 21.10°C, higher than the peak of 21.09°C reached in August 2023 and much higher than the 20.99°C peak reached in March 2016.

As latent heat buffer shrinks, Arctic sea ice could melt away quickly

As illustrated by the image below, sea ice was very thin near the North Pole on January 24, 2024, indicating there is very little left of the latent heat buffer constituted by the sea ice to consume incoming heat.

And even more ominously, Arctic sea ice thickness declined dramatically in a few days time, as indicated by the compilation image below, with images from the University of Bremen.

For the time of year, Arctic sea ice extent is currently still extensive, compared to earlier years, which is a reflection of more water vapor in the atmosphere and more precipitation. While sea ice extent is relatively large, Arctic sea ice volume now is among the lowest of all years on record for the time of year, as illustrated by the image below. Volume = extent x thickness, so low volume and relatively large extent means that sea ice is very thin.

As more sunlight starts reaching the Northern Hemisphere, in line with seasonal changes, Arctic sea ice extent can be affected dramatically and abruptly, as illustrated by the image below.

Furthermore, much of the thicker sea ice is located off the east coast of Greenland, as illustrated by the image below. This means that this sea ice is likely to melt away quickly as temperatures rise in line with seasonal changes.

Without the buffer constituted by thicker sea ice, such an influx of ocean heat could destabilize hydrates contained in sediments at the seafloor of the Arctic Ocean, resulting in eruptions of huge amounts of methane.

[ The buffer is gone - Latent Heat Tipping Point crossed ]

Given methane's very high immediate global warming potential (GWP), this could push up temperatures dramatically and rapidly.

[ potential methane rise, from earlier post ]

[ from the Extinction page ]

The above image shows a polynomial trend added to NOAA globally averaged marine surface monthly mean methane data from April 2018 to November 2022, pointing at 1200 ppm CO₂e (carbon dioxide equivalent) getting crossed in 2027.

A rise in methane concentrations alone may suffice to cause the Clouds Tipping Point, at 1200 ppm CO₂e, to get crossed. The resulting clouds feedback could on its own cause the temperature to rise by a further 8°C.

When further forcing is taken into account, crossing of the Clouds Tipping Point could occur even earlier than in 2027.

The image on the right illustrates how a huge temperature could unfold and reach more than 18°C above pre-industrial by 2026.

With such a rise, the temperature is likely to keep rising further, with further water vapor accumulating in the atmosphere once the water vapor tipping point gets crossed, as discussed in an earlier post and at Could Earth go the same way as Venus?

As a rather sobering footnote, humans will likely go extinct with a 3°C rise and most life on Earth will disappear with a 5°C rise, as illustrated by the image below, from an earlier post.

[ from earlier post ]

Climate Emergency Declaration

Links

• NASA - Goddard Institute for Space Studies (GISS) Surface Temperature Analysis
https://data.giss.nasa.gov/gistemp

• Ubiquitous acceleration in Greenland Ice Sheet calving from 1985 to 2022 - by Char Greene et al. https://www.nature.com/articles/s41586-023-06863-2
discussed at facebook at:
https://www.facebook.com/groups/arcticnews/posts/10161223121909679

• Danish Meteorological Institute - Arctic sea ice volume and thickness
https://ocean.dmi.dk/arctic/icethickness/thk.uk.php

• Cold freshwater lid on North Atlantic
https://arctic-news.blogspot.com/p/cold-freshwater-lid-on-north-atlantic.html

• Latent Heat
https://arctic-news.blogspot.com/p/latent-heat.html

• Pre-industrial
https://arctic-news.blogspot.com/p/pre-industrial.html

• Could Earth go the same way as Venus?

https://arctic-news.blogspot.com/p/could-earth-go-same-way-as-venus.html

Tuesday, April 4, 2023

IPCC keeps downplaying the danger even as reality strikes

Record hot sea surface

The daily sea surface temperature (SST) between 60°South and 60°North was at a record high on April 2, 2023, i.e. the highest temperature in the NOAA record that started in 1981, as illustrated by the above image. The black line shows this year's SST, up to April 2, 2023. The orange line shows last year's SST, i.e. 2022. The thicker grey line shows SST in the year 2020, when annual temperatures on land and ocean reached a record high, since 2020 was an El Niño year.

This record high sea surface temperature comes as we're moving into a new El Niño, as illustrated by the image on the right, adapted from NOAA.

There are further reasons why this uptick doesn't come unexpected. The emerging El Niño looks set to coincide with high sunspots, while the 2022 Tonga submarine volcano eruption did add a huge amount of water vapor to the atmosphere, as discussed in an earlier post.

Greenhouse gas concentrations keep rising

Reducing emissions is the right thing to do, even though it comes with loss of the aerosol masking effect that causes a rise in temperatures, as discussed in an earlier post. Moreover, greenhouse gas levels aren't falling.

Global monthly nitrous oxide rose to 336.33 ppb in December 2022, as illustrated by the image on the right. A recent study found that atmospheric abundances and emissions of five CFCs (CFC-13, CFC-112a, CFC-113a, CFC-114a and CFC-115) increased between 2010 and 2020.

Carbon dioxide (CO₂) broke three records recently at Mauna Loa, Hawaii, as illustrated by the image on the right.

The daily mean (green points) rose to 423.23 ppm (parts per million) on April 12, 2023, a record high in the NOAA record for in situ measurements. The weekly mean CO₂ (red lines) was 422.54 ppm in the week that started April 2, 2023, and the monthly mean CO₂ (blue lines) was 421.00 ppm in March 2023.

Furthermore, CO₂ was as high as about 424.5 ppm in a flask measurement at Mauna Loa, Hawaii recently, as illustrated by the image on the right.

Monthly methane recently rose to above 1950 ppb at Mauna Loa, Hawaii, as illustrated by the image on the right underneath.

Globally, methane rose to 1924.99 ppb in December 2022, the highest in the NOAA globally averaged marine surface monthly mean methane record that goes back to July 1983.

The image below has a polynomial trend added based on April 2018 to December 2022 NOAA global methane data and pointing at 1200 ppm CO₂e (carbon dioxide equivalent) getting crossed in 2027.

The Clouds Tipping Point, at 1200 ppm CO₂e, could be crossed and this on its own could result in a further rise of 8°C. This tipping point could be crossed as early as in 2027 due to forcing caused by the rise in methane alone. When further forcing is taken into account, this could happen even earlier than in 2027.

NOAA's 1924.99 ppb for the December 2022 global methane mean translates into 385 ppm CO₂e when using a 1-year GWP of 200 for methane.

So, adding this 385 ppm CO₂e to 424.5 ppm CO₂ would leave just 390.5 ppm CO₂e for further forcing, before the Clouds Tipping Point would get crossed, as the image on the right illustrates.

Methane at higher altitude can reach even higher levels than NOAA's global marine surface data. As the image further above shows, monthly methane recently rose to above 1950 ppb at Mauna Loa, Hawaii.

Further changes such as caused by sea ice loss and changes in aerosols can also speed up the temperature rise.

[ see the Extinction page ]

Vast amounts of ocean heat are headed to invade the Arctic. Last year, North Atlantic sea surface temperatures reached a record high of 24.9°C in early September. The continuing rise of ocean heat threatens to trigger massive loss of sea ice and eruptions of methane from the seafloor of the Arctic Ocean, as has been described many times before, such as in this post and in this post.

All this is pushing up temperatures and will likely keep pushing up temperatures even further over the next few years. To say that the situation is dangerous is a vast understatement.

Politicians keep downplaying the danger

Meanwhile, the Intergovernmental Panel on Climate Change (IPCC) is reading the Synthesis Report of its 6th Assessment Report line by line, asking for approval from politicians who seek to downplay such dangers. "There are multiple, feasible and effective options to reduce greenhouse gas emissions and adapt to human-caused climate change, and they are available now" says the IPCC in an earlier news release with the title Urgent climate action can secure a liveable future for all.

The IPCC was created in 1988 by politicians and set up under the UNEP and WMO to provide politicians with the best-available scientific analysis on climate change. Yet, emissions have kept rising ever since, even accelerating, and the situation has continued to become ever more dire.

Let's face it, the IPCC is an instrument used by politicians to keep downplaying the danger, even as reality strikes it in the face as to how dire the situation is. Politicians control the IPCC and politicians have proven to be prone to make deals in which they sell out climate action. Politicians have forfeited their chance to influence the process.

Climate action flowchart

In conclusion, politicians should be kept as much as possible out of the climate picture. We, the people, should support communities seeking effective climate action. Below is a flowchart showing how climate action can be achieved without politicians.