Cryosphere in peril: Calls by Scientists, President of Chile, Prime Minister of Iceland, UN Chief to phase out Fossil Fuels at COP28

Before attending COP28 in Dubai, UN Secretary General Antonio Guterres did a flying vist to Antarctica with Gabriel Boric, President of Chile, to see and talk with polar scientists on the changes to the Cryosphere and Antarctica in particular.

 "What happens in Antarctica doesn’t stay in Antarctica. " Guterres said.

"Without changing course, we’re heading towards a calamitous three-degree Celsius temperature rise by the end of the century. That means losing the West Antarctica Ice Sheet almost entirely. This alone could ultimately push up sea levels by around five meters." said the UN Chief.

The International Cryosphere Climate Initiative published its latest State of the Cryosphere report 2023 on 16 November 2023, outlining in 6 detailed chapters covering the changes and impacts of Ice Sheets, Mountain Glaciers and Snow, Sea Ice, Permafrost and Polar Oceans. The report included a forward by the President of Chile and Prime Minister of Iceland calling for a phaseout of fossil fuels to limit damages to the cryosphere, and consideration of the issue in the Global Stocktake at COP28. 

Antarctic ice mass accelerating according to GRACE reanalysis, Pine Island Glacier in sustained retreat

The continent of Antarctica is a land of complexity and paradox, especially when talking about climate change. It is our driest and coldest desert on the planet but locks up an enormous amount of fresh water in it's thick ice sheets. The southern ocean surrounds the continent, insulating it from warmer latitudes, but those currents also bring warmer waters from the tropics to interact with the giant ice shelves around the continent.

And of course there is the paradox of Antarctic sea ice which is recording record sea ice extent over recent years due to the complex winds, currents and dynamics of melt water.

Sea ice growth or melt does not affect sea level rise. We need to look at what the great Ice sheets are doing to determine whether they are accelerating mass loss and contributing to sea level rise.

The GRACE satellites provide us with a remote measuring tool for ice mass balance, but like all tools it comes with certain biases built in. The job of the scientist is to analyse and correct for these biases.

Greenland Melting detected during Winter a climate change concern

Satellite data for the first several weeks of 2013 is showing that melting is occurring in south east Greenland. In summer this would be expected, but January-February is the dead of winter. Some portions of Greenland have experienced more than 30 days of melting since the start of this year, a worrying trend.

According to email correspondence with Ted Scambos from National Snow and Ice Data Centre (NSIDC) sent to Tom Yulsman, all of Greenland has been 2 to 6 degrees C warmer than the 30 year mean. Tom quotes Ted Scambos on his blog: "Air temperatures along the southeastern coast for the period Feb 10 – 15 are running 2 to 6 C above normal. Nuuk, the capital, on the very southern west coast, is currently just a couple of degrees below freezing."

Related: Is Climate Change causing an exponential rate of Ice sheet Mass Loss, sea level rise? | Global Warming threshold for Greenland Ice Sheet collapse reduced to 1.6 degrees C

Is Climate Change causing an exponential rate of Ice sheet Mass Loss, sea level rise?

Climate scientist James Hansen and his colleague Makiko Sato have released a new discussion paper with updated data on ice sheet mass loss from Greenland and Antarctica, with implications for possible multi-metre sea level rise this century. It makes for some interesting reading - there is a link to Hansen's website and the paper at the end.

The thesis that Hansen has put forward for several years is that Ice Sheet collapse is a non-linear process: that with the inclusion of amplifying climate feedbacks it is likely to follow an exponential rate of acceleration - a doubling rate. It might be a 10 year doubling time, or less. This will lead to extensive sea level rise, perhaps in the order of 5 metres this century.

But accurate data measurements of ice mass loss via laboriously estimating mass input and output has only been available since the early 1990s, and accurate satellite measurements (Gravimetry) via the GRACE satellites since 2000.

What these measurements show is that ice mass loss from both Greenland and Antarctica are accelerating, but the data for the time period is still too short to determine whether ice sheet mass loss will follow a somewhat linear path, or an exponential path doubling every 10 years or shorter time period.

Caption: Figure 2: Greenland (a) and Antarctic (b) mass change deduced from gravitational field measurements by Velicogna (2009) and best-fits with 5-year and 10-year mass loss doubling times. From NASA: Earth's Climate History: Implications for Tomorrow Hansen and Sato July 2011

Update 14 Jan 2013: Matt Owens from Fairfax Climate Watch had a similar idea in reviewing Hansen's discussion paper. Read his initial analysis: Sea level rise could crimp GDP; US direct losses could top 1/4 trillion per year during 2040-2050. On 11 January 2013 he updated his analysis with a new article: Surprising negative feedback could mean epic disaster. Both are worthwhile reading.

Global Warming on West Antarctic Ice Sheet three times the global average

The West Antarctic Ice Sheet is warming at three times the global average, according to temperature measurements at Byrd Polar Station. This has implications for the melting of the West Antarctic Ice sheet (WAIS) and sea level rise.

The West Antarctic Ice Sheet is inherently unstable due to it's grounding in a deep depression below sea level. Warm Southern ocean currents are already reducing ice shelves holding back ice discharge from glaciers. As these ice shelves are undermined and break up it will allow significant acceleration of glacier discharge increasing the rate of sea level rise.

Lead study author David H. Bromwich from Ohio State University said:

"Our record suggests that continued summer warming in West Antarctica could upset the surface mass balance of the ice sheet, so that the region could make an even bigger contribution to sea level rise than it already does," said Bromwich.

"Even without generating significant mass loss directly, surface melting on the WAIS could contribute to sea level indirectly, by weakening the West Antarctic ice shelves that restrain the region's natural ice flow into the ocean."

Related: Global warming in Antarctica: Thwaites and Pine Island Glaciers | Waking the giant: Global Warming in the Weddell Sea | Southern Ocean warming impact on Antarctic Ice Sheet and global sea level

Climate change connection between Global temperatures, ice volume and sea level

There is a rapid response connection between polar temperature changes, ice volume and sea leavel according to a new method of dating of sea level records and comparing them with temperature data and ice core records for the last 150,000 years.

Previously the dating of ice-volume changes relied on the ‘Red Sea relative sea-level (RSL) record’. However this dating method did not have independent age control which inhibited detailed comparison with other well-dated climate parameters, such as temperature or CO2 records from ice cores from Greenland and Antarctica. The new method of dating the RSL record used Mediterranean data from radiometric (Uranium-series) dating of cave deposits which could be applied to the last glacial cycle reaching back 150,000 years, providing a continuous sea-level record with excellent independent age control.

According to the study sea level rise reached speeds of "at least 1.2 metres per century during all major episodes of ice-volume reduction" in the last 150,000 years.

One of the study authors, Professor Elco Rohling from the National Oceanography Centre Southampton said: "This is the first time that these rates could be measured for any other period than the end-of-ice age 'terminations/deglaciations'. Although it is always hard to step from palaeo reconstructions to future projections, it suggests that when significant ice-volume adjustments happen, they are rarely slow."

Southern Ocean warming impact on Antarctic Ice Sheet and global sea level rise

Climate change is causing the southern ocean to warm and freshen which will melt ice shelves and glacier tongues affecting glacier discharge and producing Antarctic Ice Sheet mass loss and global sea level rise. A new study shows that small temperature changes of the Southern Ocean can contribute to far-reaching changes on the Antarctic ice sheet that could lead to substantial future sea-level rise.

Related: Waking the giant: Global Warming in the Weddell Sea, West Antarctic Ice Sheet and sea level rise | Attenborough warns of ice shelf destruction in Antarctica | Global Warming in Antarctica: Thwaites and Pine Island Glaciers accelerating, West Antarctic Ice Sheet losing mass

Greenland Ice Sheet experiences unprecedented surface melt

Surface melt on the Greenland ice sheet reached up to 97% of the ice sheet area by July 12, an unprecedented level of melting, according to readings gathered and cross-referenced from three different satellites by several scientists.

Satellite measurements showed that about 40 percent of the ice sheet had undergone thawing at or near the surface on July 8, but over the subsequent 4 days the melting had dramatically accelerated to cover an estimated 97 percent of the ice sheet surface by July 12. This was the largest area seen thawing ever measured on the Greenland ice sheet by satellite measurements.

Waking the giant: Global Warming in the Weddell Sea, West Antarctic Ice Sheet and sea level rise

Warm ocean currents are projected to melt the Filchner-Ronne Ice Shelf in the Weddell Sea area of Antarctica opening instabilities in the West Antarctic Ice sheet (WAIS) which will impact global sea level rise. Climate change is waking up the sleeping giant of Antarctica.

Significant scientific research has been published in recent weeks on the impact of global warming on changing wind patterns and southern ocean currents and the flow-on impact on Antarctic ice shelves and glaciers. The most recent studies reveal the potential instability of the Filchner-Ronne Ice Shelf in the Weddell Sea area. But the real questions to be asked concern the long term stability of the West Antarctic Ice Sheet (WAIS) and how rapidly it could collapse raising global sea levels by up to 6 metres.

I highlighted in November 2011 that the Thwaites and Pine Island Glaciers accelerating, West Antarctic Ice Sheet losing mass in the Amundsen Sea area. Now climate researchers of the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association studying the opposite side of the West Antarctic Ice Sheet (WAIS) in the Weddell Sea area have discovered a mechanism which will drive warm ocean water towards the coast in the later decades of this century, allowing a higher rate of basal melting - the melting from underneath of ice shelves and glaciers by warmer ocean currents - leading to greater discharge of ice from the icesheet.

Another research team has found a large deep basin, about 20,000 square kilometres in size and up to 2 kilometres deep, underneath the ice sheet in the Weddell Sea area, which makes the ice sheet inherently unstable if pinion points for the ice shelf retreat and warmer water enters the basin.

Global Warming threshold for Greenland Ice Sheet collapse reduced to 1.6 degrees C

New research from the Potsdam Institute for Climate Impact Research and Universidad Complutense de Madrid has lowered the best estimate for the irreversible collapse of the Greenland Ice Sheet down to 1.6 °C, making the ice sheet more vulnerable than previously thought to global warming. The previous best estimate was 3.1 °C. As we currently have 0.8 °C of global warming, by the middle of the century we could easily pass this new threshold unleashing an ultimate sea level rise of several metres.

Already we have seen record summer melting in Greenland in 2010, and near record mass loss in 2011. According to NOAA the melt season in 2011 lasted up to 30 days longer than average and it affected 31 percent of the ice sheet surface, making 2011 one of just three years since 1979 where melt area exceeded 30 percent. Polar regions are warming much faster and to a greater degree than any other latitude on earth.

Attenborough warns of ice shelf destruction in Antarctica

UK Naturalist and documentary maker David Attenborough has warned about the implications of melting ice sheets in the polar regions but emphasised the changes under way in Antarctica "is likely to have the most dramatic effects of all".

His comments were made in a November 2011 article in the BBC Radio Times reported by the Independent newspaper. While the title of the Independent newspaper article - Warning over melting ice at North Pole - places emphasis on processes in the Arctic, the important statement by Attenborough is about the collapse of ice shelves fringing Antarctica and the implications for the West Antarctic Ice Sheet.

Global Warming in Antarctica: Thwaites and Pine Island Glaciers accelerating, West Antarctic Ice Sheet losing mass

Scientists have been studying the climate change impacts on ice shelfs and glaciers for some time in Antarctica, and particularly around the Antarctic Peninsula where there is substantial warming occurring increasing ice shelf melt and the speed and discharge of glaciers. The most recent studies predict a faster retreat for the Thwaites Glacier and that warm ocean currents are already speeding the melting of the Pine Island Glacier and Ice Shelf and Getz Ice Shelf. A NASA Icebridge flight detected a major new rift in the Pine Island ice shelf on October 14 - the start of the calving of a massive iceberg. A recent paper in Nature Geoscience discusses the Stability of the West Antarctic ice sheet in a warming world and the likelihood of collapse that would raise sea level by more than three metres over the course of several centuries or less.

Related: The Wilkins ice Bridge collapsed in April 2009 as Polar regions felt the heat of climate change. I reported as far back as 2004 that warming in Antarctica was cause for concern with ocean food chain crashing due to Antarctic warming. More recently in April 2011 I discussed Penguin numbers suffering with krill decline due to Global Warming.

Greenland melting in 2011 well above average with near-record mass loss

Professor Marco Tedesco from the City College of New York reports that extreme melting continues from the Greenland Ice sheet this year with close-to-record simulated surface mass balance, bare ice exposure, albedo and runoff anomalies. He warned that glaciers could undergo a self-amplifying cycle of melting and warming that would be difficult to halt.

Related: Record summer melting in 2010 | Greenland sets a new melt record in 2010 - sea levels to rise

Record summer melting in Greenland 2010

I reported in January that Greenland sets a new melt record in 2010 - sea levels to rise. This image from the NASA Earth Observatory Image of the day site shows clearly the level of melting. During 2010 there was little summer snow to replenish the losses, with melting starting early and finishing much later resulting in a melting period 50 days longer than average.

The image shows 2010 compared to the average number of melt days per year between 1979 and 2009. It was assembled from microwave data from the Special Sensor Microwave/Imager (SSM/I) of the Defense Meteorological Satellites Program.

Read more at Earth Observatory: Record Melting in Greenland during 2010

Greenland sets a new melt record in 2010 - sea levels to rise

The chilly fact is that the Greenland ice cap is melting at an accelerated rate. The big melt achieved a new record in 2010 according to new research.

"This past melt season was exceptional, with melting in some areas stretching up to 50 days longer than average," said Dr. Marco Tedesco, Director of the Cryosphere Processes Laboratory at the City College of New York (CCNY - CUNY), who is leading a project studying variables that affect ice sheet melting. "Melting in 2010 started exceptionally early at the end of April and ended quite late in mid- September."

La Niña brings some rain, as Global Climate hots up

One of the important weather factors in the Pacific basin affecting global weather but particularly Pacific Rim countries is the El Niño/Southern Oscillation (ENSO). El Niño and La Niña are caused by a change in sea surface temperatures across the Pacific Ocean which affects trade wind patterns which bring rain and drought to regions around the Pacific and further afield. A La Niña condition has been developing since February 2007 and is likely to last to April 2008.

Related: El Nino-Southern Oscillation (ENSO)

La Niña operating until April 2008

In November/December 2007 we are experiencing La Niña with sea surface temperatures in the eastern tropical Pacific below average, and temperatures in the western tropical Pacific above average. La Niña brings rain to Indonesia and Australia and drought to the southwest of the United States, western Mexico, Peru and Chile. Effects are typically opposite to those associated with El Niño.

The Southern Oscillation has a global impact. NASA describes the effect as:

"Globally, La Niña is characterized by wetter than normal conditions west of the equatorial central Pacific over northern Australia and Indonesia during the northern hemisphere winter, and over the Philippines during the northern hemisphere summer. Wetter than normal conditions are also observed over southeastern Africa and northern Brazil, during the northern hemisphere winter season. During the northern hemisphere summer season, the Indian monsoon rainfall tends to be greater than normal, especially in northwest India. Drier than normal conditions are observed along the west coast of tropical South America, and at subtropical latitudes of North America (Gulf Coast) and South America (southern Brazil to central Argentina) during their respective winter seasons."

Australia: Higher than average temperatures and rainfall predicted

The widespread rains in Victoria and New South Wales over the last week were probably partly induced by La Niña. The POAMA model run daily at the Australian Bureau of Meteorology predicts "La Niña conditions to remain over the coming months, persisting until around April 2008." Read more about Australian rainfall patterns during La Niña events.

The Bureau of Meteorology is predicting higher than average temperatures over much of southern Australia from January to March 2008. The temperature on New Years Eve in Melbourne is predicted to be 38 degrees. There is also a greater chance for higher than the median rainfall "in a large area extending from southeast Queensland across both the northern inland and east of NSW. The southwest of WA also has similar chances, although it's a seasonally dry time of the year in this part of the country."

For North and South America "La Niña is the diva of drought,” explained Bill Patzert of NASA’s Jet Propulsion Laboratory. “It keeps the Pacific jet stream farther north, toward Oregon, Washington, and Canada, so the U.S. Southwest and Southeast get less moisture.”

Warmest Decade on Record

The World Meteorology Organisation announced in a press release on 13 December that the decade of 1998-2007 is the warmest on record. "The global mean surface temperature for 2007 is currently estimated at 0.41°C/0.74°F above the 1961-1990 annual average of 14.00°C/57.20°F." The statement also detailed "the record-low Arctic sea ice extent...., a relatively small Antarctic Ozone Hole; development of La Niña in the central and eastern Equatorial Pacific; and devastating floods, drought and storms in many places around the world."

"2007 global temperatures have been averaged separately for both hemispheres. Surface temperatures for the northern hemisphere are likely to be the second warmest on record, at 0.63°C above the 30-year mean (1961-90) of 14.6°C/58.3°F. The southern hemisphere temperature is 0.20°C higher than the 30-year average of 13.4°C/56.1°F, making it the ninth warmest in the instrumental record since 1850."

According to the WMO statement "Australia recorded its coldest ever June with the mean temperature dropping to 1.5°C below normal." and "while conditions were not as severely dry as in 2006, long term drought meant water resources remained extremely low in many areas. Below average rainfall over the densely populated and agricultural regions resulted in significant crop and stock losses, as well as water restrictions in most major cities."

Sea Level Rise and Greenland Ice melt Accelerating

The WMO highlighted that sea level continues to rise "substantially above the average for the 20th century of about 1.7 mm per year." According to satellite measurements "global averaged sea level has been rising at about 3 mm per year" since 1993. This comes hot on the news that the melting of the Greenland icecap is accelerating according to study by the Steffen Research Group from the University of Colorado at Boulder. "The amount of ice lost by Greenland over the last year is the equivalent of two times all the ice in the Alps, or a layer of water more than one-half mile deep covering Washington, D.C." said lead climate scientists Konrad Steffen. "The more lubrication there is under the ice, the faster that ice moves to the coast," said Steffen. "Those glaciers with floating ice 'tongues' also will increase in iceberg production." Greenland ice melt currently contributes to global sea levels by about 0.5 millimeters per year. Some climate scientists like James Hansen believe the Greenland ice sheet may disintegrate within 100 years leading to a sea level rise of several metres.

Sources:

* NASA Earth Observatory La Nina for November. See also from February 2007 El Nino May Be Morphing to La Nina and in October 2007 La Nina Strenghtens in Autumn 2007
* NASA Earth Observatory La Niña Factsheet
* Bureau of Meteorology El Nino-Southern Oscillation (ENSO)
* Bureau of Meteorology Dec 17, 2007 - Warmer season favoured in southern Australia
* Bureau of Meteorology Dec 17, 2007 - Mixed March quarter rainfall outlook
* World Meteorological Organization Dec 13, 2007Press Release No 805
* NASA Earth Observatory - Media Alert Dec 11, 2007 GREENLAND MELT ACCELERATING, ACCORDING TO CU-BOULDER STUDY

Arctic Sea Ice heading for Rapid Disintegration: Greenland Ice Sheet melting

Arctic summer sea ice is headed towards rapid disintegration as early as 2013, a century ahead of the International Panel on Climate Change (IPCC) projections, according to 'the Big Melt' (PDF), a new review of recent scientific literature on climate change produced by www.carbonequity.info. We have gone past the tipping point for Arctic sea ice and now we watch the disintegration of the Greenland and the West Antarctic ice sheets which will result in catastrophic changes in sea level of 5 metres or more in the next 100 years.

NASA Climatologist Predicts Disastrous Sea Level Rise

In an interview on Australian ABC Television program, The 7.30 Report, James Hansen, a prominent NASA climatologist, predicted the likelihood that the earth will pass a tipping point resulting in Sea Level Rise of up to a metre every 20 years. The trigger for this is an extra degree of global warming resulting in the runaway melting of the Greenland and West Antarctic Ice sheets.

According to Hansen "the problem is that the climate system in general has a lot of inertia and that means that it takes time for the changes to begin to occur but then, once they do get under way, it becomes very difficult to stop them and that is true in spades for the ice sheets. If we once begin to disintegrate it will become very difficult, if not impossible, to stop them and we are beginning to see now on both Greenland and west Antarctica disintegration of those ice sheets. They're both losing ice at a rate of about 150 cubic kilometres per year and that's still not a huge sea level rise."

Catastrophic Climate Change may be Inevitible unless Drastic Steps are Taken

A report by Friends of the Earth Australia warns that catastrophic climate change may be inevitable unless dramatic steps are taken to reduce emissions. While the scientific community have finally consensed that human induced climate change is an unequivical reality with the release of the International Panel on Climate Change (IPCC) scientific report on 2 February 2007, the survey of recent scientific research by FOE(Australia) indicates the IPCC climate change models may be very conservative and underestimate feedback effects of climate change.

The report was prepared by the Carbon Equity Project, and surveys climate data released by scientists in the last couple of years. Examining the risks and probabilities of catastrophic changes to the climate, the report concludes that annual greenhouse gas reductions of 4 to 5% a year must begin by the end of the decade if we are to have a reasonable chance of preventing disaster.

Greenland Ice Sheet melting faster than expected

Scientists have measured a significant decrease in the mass of the Greenland ice cap, using data from satellites that measures movement in Earth's mass. A team led by Dr. Isabella Velicogna of the University of Colorado, Boulder, found that Greenland's ice sheet decreased by 162 (plus or minus 22) cubic kilometers a year between 2002 and 2005. This is higher than all previously published estimates, and it represents a change of about 0.4 millimeters (.016 inches) per year to global sea level rise.

The first direct, comprehensive mass survey of the entire Greenland ice sheet updates findings published in the journal Geophysical Research Letters. Data was collected from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment (GRACE) satellite.