Experts: Ice-Sheet Melt Estimates Still Highly Uncertain
Estimates used by climate scientists to predict the rate at which the world’s ice sheets will melt are still uncertain despite advancements in technology, new research shows.
These ice sheet estimates feed directly into projections of sea-level rise resulting from climate change.
They are made by measuring how much material ice sheets are gaining or losing over time, known as mass balance, to assess their long-term health.
Snowfall increases the mass of an ice sheet, while ice melting or breaking off causes it to lose mass, and the overall balance between these is crucial.
Although scientists now have a much better understanding of the melting behavior of ice sheets than they did in previous decades, there are still significant uncertainties about their future melt rates, researchers found.
The new study, published in the scientific journal Earth-Science Reviews, shows that despite recent advances in computer modeling of ice sheets in response to climate change, there are still key deficiencies in the models used to estimate the long-term health of ice sheets and related global sea-level predictions.
Improving these estimates could prove vital to informing the scale of response needed to mitigate the potential impacts of climate change.
Edward Hanna, Professor of Climate Science and Meteorology at the University of Lincoln, UK, co-ordinated the research in co-operation with a leading international group of glaciologists.
Professor Hanna said:
“The ice sheets are highly sensitive indicators of climate change, but despite significant recent improvements in data and knowledge, we still don’t understand enough about how rapidly they are likely to lose mass during and beyond the current century.
“Enhanced observations of ice sheets, mainly from satellite data fed into improved computer simulations, are vital [in helping] refine predictions of future sea-level rise that will result from continued global warming. They are urgently needed to assist climate adaptation and impact planning across the world.”
In the last decade, the Antarctic and Greenland ice sheets have overtaken thousands of smaller glaciers as the major contributors to rising sea levels—it is thought that combined, the sheets contain enough ice to raise global sea levels by as much as 65 meters.
However, while some estimates project a contribution of as much as one and a half meters from Antarctica to global sea-level rise by 2100, others suggest only a few tens of centimeters contribution.
The researchers say there is a pressing need for further research that involves enhanced satellite and ground-based observations, together with more sophisticated, interactive computer models that combine ice masses, the atmosphere, ocean, and solid Earth systems.
Their study involved analysis of recent estimates of the ice sheet and glacier mass balance, as well as highlighting recent advances and limitations in computer-model simulations of ice sheet change as an important basis for future work.
The World Climate Research Programme, the Scientific Committee on Antarctic Research and the International Arctic Science Committee part-sponsored the research.
Read more at Phys.org
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Jerry
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Enhanced observations of ice sheets, mainly from satellite data fed into improved computer simulations, are vital [in helping] refine predictions of future sea-level rise that will result from continued global warming. They are urgently needed to assist climate adaptation and impact planning across the world.”
This article is just more climate alarmism garbage.
First there is no way of predicting whether the globe will warm or cool.
Second the oceans are rising at rate of approximately 2.5 mm a year and have been for 20,000 years. There is no imminent threat to our coastal cities and there is nothing indicating that will change.
The climate is driven by 6 main factors that are interconnected in complex ways by 24 systems of which science has little or no data on or understanding of making it impossible to model or predict. The inherent complexity ensures the climate will always be changing and nothing man does impacts.
We don’t need more expensive inaccurate computer programs, we need temperature, precipitation and water vapor from rural ground weather stations and ocean stations.
We have little or no data for the ice caps, tundra, forests, mountains, grasslands, jungles, deserts and oceans. The temperature data is artificially high because the lack of rural ground weather stations.
Climate science is in it’s infancy and the extent of our knowledge is extremely limited at this point in history.
The present climate alarmists are going to judged harshly by future generations.
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tom0mason
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👍 Well said Jerry.
Climate science is in it’s infancy, some of the reports (like this one) are infantile.
And don’t forget that there are very few official weather stations on the great continent of Africa.
Africa, a continent that North America, including United States, Canada, Mexico, and Greenland, could easily fit inside Africa with plenty of room left to add Central America, Argentina, Chile, and Bolivia too. (see http://bl.ocks.org/zanarmstrong/raw/caa2da1ea1558cdc3357/ )
As the BBC reports here (https://www.bbc.co.uk/news/business-41967241 ) in 2017,
Many of the stations are in poor condition with poor maintenance and calibration records.
So how is the temperature of this vast area made for the Climate Models™ — effectively they just guess! (but they say they interpolate, extrapolate and homogenize from ‘known’ weather station data!)
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jerry krause
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Hi Jerry,
First you state: “Second the oceans are rising at rate of approximately 2.5 mm a year and have been for 20,000 years. There is no imminent threat to our coastal cities and there is nothing indicating that will change.”
Then you state: “We have little or no data for the ice caps, tundra, forests, mountains, grasslands, jungles, deserts and oceans. The temperature data is artificially high because the lack of rural ground weather stations.We have little or no data for the ice caps, tundra, forests, mountains, grasslands, jungles, deserts and oceans. The temperature data is artificially high because the lack of rural ground weather stations.”
Have you considered the following. There are about 1400 USA RAWS sites and more than a 100 USA USCRN sites.
https://principia-scientific.com/the-corvallis-or-uscrn-site-a-natural-laboratory/
https://principia-scientific.com/the-corvallis-or-uscrn-site-a-natural-laboratory-part-two/
https://principia-scientific.com/the-corvallis-or-uscrn-site-a-natural-laboratory-part-three/
https://principia-scientific.com/the-corvallis-or-uscrn-site-a-natural-laboratory-part-four/
https://principia-scientific.com/the-corvallis-or-uscrn-site-a-natural-laboratory-part-five/
Yet, you seem to expect a reader to accept that we know sea levels have been changing 2.5mm per year for 20000 years. At how many sites were sea levels being measured 20000 years ago?
I refuse to accept any measurements until there were standards of length, temperature, etc. and the instruments capable of actually measuring such factors. And even than, I would like to go to an ocean shore, stick a meter stick in a sand bottom and observe the range of the sea level that occurs during, say, 15 minutes.
What is nonsense is that a sea level can be ever measured to 2.5mm, now or 20000 years ago. Or a temperature to even a degree when it is observed that the air temperature can regularly change by 6 , or so, degrees Celsius during one hour, an hour after sun rise, and during one hour, an hour before sun set, at many land based site to which you have been referred.
Have a good day, Jerry
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Jerry
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According to Heartland Institute the oceans have risen at a rate of 6mm /year (400 ft./20000 years) since the last ice age. I apologize for the math error.
https://www.heartland.org/news-opinion/news/data-indicate-theres-no-need-to-panic-about-rising-seas
Your links are mainly to urban sites which confirms what I stated and the majority of the temperature data used by the IPCC is computational and/or parameterized which means they are made up.
1400 sites is far from adequate for a land mass the size of the US. The rest of world has even fewer weather stations than the US which is part of the reason the IPCC’s Climate Models are consistently inaccurate besides the fact the GCM is totally inadequate to accommodate the extreme number of variables.
Mr. Krause you would be wise to read TomOmason’s comment.
The reality is climate science is in it’s infancy and we need data not computer programs which are incapable of incorporating the vast array of variables we have yet quantified.
Good day.
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jerry krause
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Hi Jerry,
You wrote: “Your links are mainly to urban sites.”
Clearly you never clicked on a link or you would seen an Image which clearly not of a urban site. The ‘Corvallis, OR’ is how the USCRN project identified the remote natural site about 10 miles south of this city.
Big time mistake you have made which I hope hurts your credibility.
Have a good day, Jerry
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jerry krause
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Hi Jerry,
Must correct my mistake. I wrote: “Or a temperature to even a degree when it is observed that the air temperature can regularly change by 6 , or so, degrees Celsius during one hour, an hour after sun rise, and during one hour, an hour before sun set, at many land based site to which you have been referred.”
The ‘6 , or so, degrees Celsius’ should be ‘6 , or so, degrees Fahrenheit’.
Have a good day, Jerry
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Jerry
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Your comments do nothing to change my belief that the average global temperature is not rising or the science community has the ability to accurately model or predict the climate.
By the way the 1400 US sites indicate a cooling trend not a warming trend.
Tony Heller of realclimatescience.com regularly produces graphs indicating as much.
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