Tag: sea ice

“Beast from the East”

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Newly open water in the Arctic — Vladimir Lugai

The April snow falling on fruit blossoms in Europe these days may be directly connected to the loss of the sea ice in the Barents Sea in the Arctic. That was certainly the case in 2018 when the sudden cold spell known as “Beast from the East” descended on the mid-latitudes of the continent…

They are diligently stoking thousands of bonfires on the ground close to their crops, but the French winemakers are fighting a losing battle. An above-average warm spell at the end of March has been followed by days of extreme cold, destroying the vines with losses amounting to 90 percent above average. The image of the struggle may well be the most depressingly beautiful illustration of the complexities and unpredictability of global climate warming. It is also an agricultural disaster from Bordeaux to Champagne.

It is the loss of the Arctic sea-ice due to climate warming that has, somewhat paradoxically, been implicated with severe cold and snowy mid-latitude winters…

“What we’re finding is that sea-ice is effectively a lid on the ocean. And with its long-term reduction across the Arctic, we’re seeing increasing amounts of moisture enter the atmosphere during winter, which directly impacts our weather further south, causing extreme heavy snowfalls. It might seem counter-intuitive, but nature is complex and what happens in the Arctic doesn’t stay in the Arctic.” says Dr. Hanna Bailey.

And it gets more complex than that. RTFA, and understand as diverse and divergent from our “common sense” on the ground as many of these events may seem, cause and effect still happens and can be analyzed. Remedies for harmful change is the difficult bit.

The oldest, thickest Arctic sea ice is melting away – shrinking the expanse of sea ice

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❝ Arctic sea ice, the vast sheath of frozen seawater floating on the Arctic Ocean and its neighboring seas, has been hit with a double whammy over the past decades: as its extent shrunk, the oldest and thickest ice has either thinned or melted away, leaving the sea ice cap more vulnerable to the warming ocean and atmosphere…

❝ Direct measurements of sea ice thickness are sporadic and incomplete across the Arctic, so scientists have developed estimates of sea ice age and tracked their evolution from 1984 to the present. Now, a new NASA visualization of the age of Arctic sea ice shows how sea ice has been growing and shrinking, spinning, melting in place and drifting out of the Arctic for the past three decades.

“Ice age is a good analog for ice thickness because basically, as ice gets older it gets thicker,” Walt Meier said. “This is due to the ice generally growing more in the winter than it melts in the summer.”…

❝ The new animation shows two main bursts of thick ice loss: the first one, starting in 1989 and lasting a few years, was due to a switch in the Arctic Oscillation, an atmospheric circulation pattern, which shrunk the Beaufort Gyre and enhanced the Transpolar Drift Stream, flushing more sea ice than usual out of the Arctic. The second peak in ice loss started in the mid-2000s…

❝ “We’ve lost most of the older ice: In the 1980s, multiyear ice made up 20 percent of the sea ice cover. Now it’s only about 3 percent,” Meier said. “The older ice was like the insurance policy of the Arctic sea ice pack: as we lose it, the likelihood for a largely ice-free summer in the Arctic increases.”

Science, knowledge, marches on inevitably. Hopefully, our understanding keeps pace. That understanding comes with an imperative to aid increasing knowledge in supplanting older, sometimes spurious understanding.

We just lost a critical climate satellite — to Congress

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❝ One of climate change’s most important biographers — a 2,700-pound satellite orbiting 450 miles above the surface of the Earth — just recorded its last data point.

Earlier this month, the National Snow and Ice Data Center announced that, after nine years and five months in orbit, the satellite known as F17 had stopped transmitting sea ice measurements. That’s not unusual — satellites in F17’s series, all named sequentially, are normally expected to last about five years, though some make it much longer. But F17’s failure could preempt the end of the series entirely…

❝ Since 1978, the satellites, each equipped with a set of passive microwave sensors, have been recording conditions on Earth, day in and day out. By measuring the amount of radiation given off by the atomic composition and structure of different substances, like ice or seawater, microwave sensing is a useful tool for pilots and military officers tracking weather conditions. Over time, these measurements can also track cumulative changes in sea ice. As early as 1999, scientists saw that sea ice cover was decreasing more quickly than it had in previous decades — and they’ve been observing similar trends ever since.

Until now, there have always been three or four satellites in the series orbiting at a time, as part of one of the country’s oldest satellite programs, the Defense Meteorological Satellite Program (DMSP). Over time, as new satellites were launched and older models went dark, overlapping data have kept the 40-year sea-ice dataset consistent…

❝ “The real problem is that there’s nothing on the horizon,” said Walter Meier, NASA researcher. “There’s nothing funded, or planned right now.”

There is one other option — but it’s sitting in a storage room somewhere on Earth. This satellite, F20, was the last of its series to be built, and was tentatively planned to launch in 2018. That plan fell through last June, when the Senate Appropriations Committee revoked funding for the DMSP, even rescinding $50 million that had been specifically designated for launching F20. Without Congressional approval, F20 is grounded.

❝ “It’s sitting there, ready to be launched,” said Meier. He pointed out that the data from the satellite series is also used to study snow cover on land, ocean currents, temperature change, drought detection, and many other natural cycles. “The benefit is beyond my own work on sea ice.”

Even the few conservatives in Congress willing to admit to scientific evidence about climate change gets their knickers bunched over questions of responsibility and reaction. So, they respond to scientific questions the same way they have for recent decades to questions of social need, education, trade, peace – you name it. Their response is Do Nothing. They’re like petulant, ignorant children who shut their eyes and try to shout down the obvious. Hoping it will go away before they’re forced to open their eyes, again.

Help out the rest of the nation with confidence enough in science and human responsibility to fight for action. Start by kicking the deadwood out of elected office. Let them try to get honest jobs for a change.

Flights rerouted around Alaska beaches crowded with walrus climate refugees

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Walrus, Odobenus rosmarus
Click to enlarge — NOAA

The plight of thousands of walruses forced to crowd on to an Alaska beach because of disappearing sea ice has set off an all-out response from the US government to avoid a catastrophic stampede.

The Federal Aviation Authority has re-routed flights, and local communities have called on bush pilots to keep their distance in an effort to avoid setting off a panic that could see scores of walruses trampled to death…

Curiosity seekers and the media have also been asked to stay away.

An estimated 35,000 walruses were spotted on the barrier island in north-western Alaska on 27 September by scientists on an aerial survey flight.

The biggest immediate risk factor for the walruses now is a stampede – especially for baby walruses – but they have been facing a growing threat from climate change, the scientists said.

The extraordinary sighting – the biggest known exodus of walruses to dry land ever observed in the Arctic under US control – arrived as the summer sea ice fell to its sixth lowest in the satellite record last month.

“Those animals have essentially run out of offshore sea ice, and have no other choice but to come ashore,” said Chadwick Jay, a research ecologist in Alaska with the US Geological Survey.

Read the whole sad article.

The only animal that our politicians worry about is the bloodsuckers who fund their endless election campaigns.

Thanks, Mike

Scientists retrieve sea ice imagery from dawn of satellite observation

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Images from the onset of the satellite age, long languishing in storage, have been recovered by University of Colorado researchers, shedding light on sea ice variations going back 50 years.

David Gallaher and Garrett Campbell have succeeded in digitizing more than 750,000 long-lost images off data tapes and black-and-white film from NASA’s early Nimbus satellite series, focusing on changes in sea ice extent in the Arctic and Antarctica.

Both scientists work in CU’s National Snow and Ice Data Center, which is part of the university’s Cooperative Institute for Research in Environmental Sciences. Their project was fueled by $550,000 in NASA funding.

The Nimbus satellite series consisted of seven spacecraft launched over a 14-year period, its primary mission to capture clouds and other atmospheric features to aid the forecasts of hurricanes and other weather events. But now the satellites’ decades-old harvest is yielding further insights for contemporary study…

The modern satellite record of sea ice goes back only to 1979.

Gallaher learned about the stored data from the early years of the seven-satellite Nimbus series — Nimbus 1 launched Aug. 28, 1964 — during a meeting of the American Geophysical Union at San Francisco in 2009.

“We found out that it was sitting down in this warehouse in Asheville, North Carolina (at the National Climatic Data Center),” Gallaher said. “We called up and said, ‘Gee, could you send us the data for the Arctic and the Antarctic?’ And they said, ‘No.’

“They said there was no way, that it was truly ‘dark data.’ It was only on these giant rolls of film, and the only way to get what we really wanted was to scan all of it,” Gallaher said. “We asked, ‘How much are we talking about?’ And they said it would fill at least a pallet and a half.’ What? Really?”

From the efforts of Gallaher, Campbell and about eight CU students logging countless hours over the past three years — working with a $40,000 Kodak scanner picked up “dirt cheap,” according to Gallagher — more than 250,000 of the recovered Nimbus images have now been made public. The painstaking process involved having to consult NASA metadata to determine the orbit of the satellite at the point each image was recorded, and from that, identify the geographic location for each image.

Images they have recovered reveal that in 1964, Antarctica showed the largest sea ice extent ever recorded there, and that just two years later, in 1966, it registered a record-low maximum sea ice extent…

“If we had information about the winds and sea surface temperatures down there, we might be able to better interpret it,” said Campbell, a project scientist. “We have not had the time and energy to look into that. We’re still in the details of extracting all the information from these images.”

An interesting by-product of the scientists’ work is that they learned of a University of Tasmania study creating a 150-year proxy record of Antarctic sea ice change, extrapolating data from methanesulphonic acid concentrations drawn from the Law Dome ice core, south of Cape Poinsett, Antarctica. That study had indicated a 20 percent sea ice decline since about 1950.

“We’re able to validate (the Tasmanian study) with 1960s Nimbus (images),” Gallaher said. “Is it the end all? We don’t know, but if you look now at their record, validated by our records, it turns out the Antarctic started a major decline in 1950s.”

Such an interesting search. You’re tired of hearing this; but, given back, say, the last thirty years, I’d get serious about a new career in computational analysis. Though I think the craft can be used with broad strokes down to the finest, narrow quizzing of scientific data, I’d probably focus on work like this.

Of course, if you want to daydream, you could end up working for Craig Venter on genomics. Woo-hoo!

Thanks, Mike

Arctic will be nearly free of summer sea ice this century

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For scientists studying summer sea ice in the Arctic, it’s not a question of “if” there will be nearly ice-free summers, but “when.” And two scientists say that “when” is sooner than many thought — before 2050 and possibly within the next decade or two.

James Overland of NOAA’s Pacific Marine Environmental Laboratory and Muyin Wang of the NOAA Joint Institute for the Study of Atmosphere and Ocean at the University of Washington, looked at three methods of predicting when the Arctic will be nearly ice free in the summer. The work was published recently online in the American Geophysical Union publication Geophysical Research Letters.

“Rapid Arctic sea ice loss is probably the most visible indicator of global climate change; it leads to shifts in ecosystems and economic access, and potentially impacts weather throughout the northern hemisphere,” said Overland. “Increased physical understanding of rapid Arctic climate shifts and improved models are needed that give a more detailed picture and timing of what to expect so we can better prepare and adapt to such changes. Early loss of Arctic sea ice gives immediacy to the issue of climate change.”

“There is no one perfect way to predict summer sea ice loss in the Arctic,” said Wang. “So we looked at three approaches that result in widely different dates, but all three suggest nearly sea ice-free summers in the Arctic before the middle of this century…”

The “trendsetters” approach uses observed sea ice trends. These data show that the total amount of sea ice decreased rapidly over the previous decade. Using those trends, this approach extrapolates to a nearly sea ice-free Arctic by 2020.

The “stochasters” approach is based on assuming future multiple, but random in time, large sea ice loss events such as those that occurred in 2007 and 2012. This method estimates it would take several more events to reach a nearly sea ice-free state in the summer. Using the likelihood of such events, this approach suggests a nearly sea ice-free Arctic by about 2030 but with large uncertainty in timing.

The “modelers” approach is based on using the large collection of global climate model results to predict atmosphere, ocean, land, and sea ice conditions over time. These models show the earliest possible loss of sea ice to be around 2040 as greenhouse gas concentrations increase and the Arctic warms. But the median timing of sea ice loss in these models is closer to 2060. There are several reasons to consider that this median timing of sea ice loss in these models may be too slow.

Taken together, the range among the multiple approaches still suggests that it is very likely that the timing for future sea ice loss will be within the first half of the 21st century, with a possibility of major loss within a decade or two.

Predictive conservatism obviously limits how far these folks are willing to stick out their necks. If you’re thoughtful about material reality, science and computational analysis, you will pay attention to the news from NOAA.

OTOH, if you’re ideologically driven and silly enough to rely on cynics paid to call themselves skeptics – Good Luck!

Landlubbers haven’t a clue about Arctic sea ice this winter

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During the Northern Hemisphere winter of 2010–2011, unusually cold temperatures and heavy snowstorms plagued North America and Europe, while conditions were unusually warm farther north. Now the U.S. National Snow and Ice Data Center (NSIDC) has reported that Arctic sea ice was at its lowest extent ever recorded for January (since satellite records began).

This image shows the average Arctic sea ice concentration for January 2011, based on observations from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) aboard NASA’s Aqua satellite. Blue indicates open water; white indicates high sea ice concentrations; and turquoise indicates loosely packed sea ice. The yellow line shows the average sea ice extent for January from 1979 through 2000…

NSIDC offered two possible explanations. One reason is the Arctic Oscillation (AO), a seesaw pattern of differences in atmospheric pressure. In “positive” mode, the AO includes high pressure over the mid-latitudes and low pressure over the Arctic, setting up wind patterns that trap cold air in the far North. In “negative” mode, air pressure isn’t quite as low over the Arctic and isn’t quite as high over the mid-latitudes. This enables cold air to creep south and relatively warm air to move north.

The AO was in negative mode in December 2010 and January 2011, according to the U.S. National Oceanic and Atmospheric Administration (NOAA). At mid-latitudes, the negative mode resulted in extremely cold temperatures and heavy snow in Europe and North America. At the same time, warm air over the Arctic impeded sea ice growth. NOAA has forecast that the AO should return to positive mode in February 2011, but for how long was unclear.

Another factor in the low Arctic sea ice extent, NSIDC explained, could be that the areas of open ocean were still releasing heat to the atmosphere. Due to its bright appearance, sea ice reflects most of the Sun’s light and heat back into space. Dark ocean water, by contrast, absorbs most of that energy and reinforces the melting process.

Both conditions are comparatively short-term in affecting climate. Not that reality means much to congenital weather whiners. Those accustomed to searching for every possible rationale to support positive cashflow for fossil fuel profiteers will steer this bit of data to whatever is this month’s Chamber of Commerce talking point.

It does allow for better understanding for folks interested in climate, meteorology and science.

Cryosat satellite ice mission returns first scientific data

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The Cryosat-2 spacecraft has produced its first major science result. Radar data from the European satellite has been used to make a map of ocean circulation across the Arctic basin.

Cryosat’s primary mission is to measure sea-ice thickness, which has been in sharp decline in recent decades. But its ability also to map the shape of the sea surface will tell scientists if Arctic currents are changing as a result of winds being allowed to blow more easily on ice-free waters.

“Nobody really knows how the Arctic is going to behave as the ice retreats, but we do anticipate that significant changes will occur,” said Dr Seymour Laxon, a Cryosat science team member from University College London, UK.

“This is just the first data, and it shows we now have the tool to monitor what is happening,” he told BBC News…

The European Space Agency (Esa) satellite was launched in April. It carries one of the highest resolution synthetic aperture radars ever put in orbit.

The instrument sends down pulses of microwave energy which bounce off both the top of the Arctic sea-ice and the water in the cracks, or leads, which separate the floes.

By measuring the difference in height between these two surfaces, scientists will be able, using a relatively simple calculation, to work out the overall volume of the marine ice cover in the far north…

And the opening months of observations have enabled the Cryosat team to build a unique map from just the radar echoes bouncing off leads.

RTFA for the details. Great work – the beginnings of completely new data to aid scientists studying climate and more.

Flat-earthers stuck into pundits who flagellate themselves over less-than-geologic time may now return to Faux Newz.

Satellites and submarines – and sea ice

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While satellites provide accurate and expansive coverage of ice in the Arctic Ocean, the records are relatively new. Satellites have only monitored sea ice extent since 1973. NASA’s Ice, Cloud, and land Elevation Satellite (ICESat) has been on the task since 2003, allowing researchers to estimate ice thickness as well.

To extend the record, Ron Kwok, NASA, and Drew Rothrock of the University of Washington, Seattle, recently combined the high spatial coverage from satellites with a longer record from Cold War submarines to piece together a history of ice thickness that spans close to 50 years.

Analysis of the new record shows that since a peak in 1980, sea ice thickness has declined 53 percent. “It’s an astonishing number,” Kwok said. The study, published online August 6 in Geophysical Research Letters, shows that the current thinning of Arctic sea ice has actually been going on for quite some time…

“We need to understand the long-term trends, rather than the short-term trends that could be easily biased by short-term changes,” Kwok said. “Long-term trends are more reliable indicators of how sea ice is changing with the global and regional climate.”

That’s why a long-term series of data was necessary. “Even decadal changes can be cyclical, but this decline for more than three decades does not appear to be cyclical,” Rothrock said…

A complete picture of sea ice requires an additional, vertical measurement: thickness. Melting affects more than just ice area; it can also impact ice above and below the waterline. By combining thickness and extent measurements, scientists can better understand how the Arctic ice cover is changing…

To put the recent decline in context, Kwok and Rothrock examined the recent five-year record from ICESat in the context of the longer history of ice thickness observed by U.S. Navy submarines.

In total, declassified submarine data span nearly five decades—from 1958 to 2000—and cover a study area of more than 1 million square miles, or close to 40 percent of the Arctic Ocean.

Kwok and Rothrock compared the submarine data with the newer ICESat data from the same study area and spanning 2003 to 2007. The combined record shows that ice thickness in winter of 1980 averaged 3.64 meters. By the end of 2007, the average was 1.89 meters.

RTFA. These are a couple of guys who let science and facts determine their conclusions. Rather than the politics of “skepticism” ideology.

As usual, what should scare the ideological skeptics is each new study, each new determination shows the intentional conservatism of peer-reviewed science has been cautious at describing the rate of climate change.

Sea ice near Greenland at lowest level in 800 years

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Special shapes Greenland potato award for climate “skeptics”

New research, which reconstructs the extent of ice in the sea between Greenland and Svalbard from the 13th century to the present indicates that there has never been so little sea ice as there is now. The research results from the Niels Bohr Institute, among others, are published in the scientific journal, Climate Dynamics.

There are of course neither satellite images nor instrumental records of the climate all the way back to the 13th century, but nature has its own ‘archive’ of the climate in both ice cores and the annual growth rings of trees and we humans have made records of a great many things over the years – such as observations in the log books of ships and in harbour records. Piece all of the information together and you get a picture of how much sea ice there has been throughout time…

In order to determine how much sea ice there has been, the researchers needed to turn to data from the logbooks of ships, which whalers and fisherman kept of their expeditions to the boundary of the sea ice. The ship logbooks are very precise and go all the way back to the 16th century. They relate at which geographical position the ice was found. Another source of information about the ice are records from harbours in Iceland, where the severity of the winters have been recorded since the end of the 18th century.

By combining the curve of the climate with the actual historical records of the distribution of the ice, researchers have been able to reconstruct the extent of the sea ice all the way back to the 13th century. Even though the 13th century was a warm period, the calculations show that there has never been so little sea ice as in the 20th century…

None of this is a surprise to anyone who follows climate science in peer-reviewed journals. OTOH, there is the crowd who gets their rocks off when a daily weather chart shows what they hope to be a contradictory anomaly.

Too bad our professional weather “skeptics” have no perception of the differences between weather and climate.