Archives par mot-clé : Ice

New Paper: Arctic Sea Ice Was Far Less Extensive Than Today During The ‘Ice Free’ Early Holocene

by K. Richard, May 23, 2019 in NoTricksZone


Biomarker evidence for Arctic-region sea ice coverage in the northern Barents Sea indicates the most extensive sea ice conditions of the last 9,500 years occurred during the 20th century (0 cal yr BP). In contrast, this region was ice free with open water conditions during the Early Holocene (9,500-5,800 years ago).

Greenland Has Been Cooling In Recent Years – 26 Of Its 47 Largest Glaciers Now Stable Or Gaining Ice

by K. Richard, May 20, 2019 in NoTricksZone


A new analysis of recent trends for the Greenland ice sheet reveals that since 2012 there has been an abrupt slowing of melt rates and a trend reversal to cooling and ice growth.
• In 2018, 26 of Greenland’s 47 largest glaciers were either stable or grew in size.
• Overall, the 47 glaciers advanced by +4.1  km² during 2018.  Of the 6 largest glaciers, 4 grew while 2 retreated.
• Since 2012, ice loss has been “minor” to “modest” due to the dramatic melting slowdown.
• Summer average temperatures for 2018 were lower than the 2008-2018 average by more than one standard deviation.
• Since 2000, the extent of the non-snow-covered areas of Greenland has increased by 500 km² per year.

Basic Science: 4 Keys to Melt Fears About Ice Sheets Melting

by William Ward, April 18, 2019 in WUWT


The world is drowning in articles about catastrophic sea level rise (SLR), reminding us that if the ice sheets melt, 260 feet of water will flood our coastal cities. We know that sea level today is 20-30 feet lower than it was at the end of the last interglacial period 120,000 years ago. We also know that sea level has risen 430 feet since the end of the last glacial maximum 22,000 years ago. Research shows this rise was not monotonic but oscillatory, and during periods over the past 10,000 years, sea level has been several meters higher than today. So, evidence supports the possibility of higher sea levels, but does the evidence support the possibility of catastrophic sea level rise from rapidly melting ice?

In this paper, basic science is used to show that catastrophic SLR from melting ice cannot happen naturally over a short period. Additionally, humankind does not possess the capability to melt a large amount of ice quickly even through our most advanced technology. This news should relieve the public, which is routinely deceived by reporting that misrepresents the facts. The public is susceptible to unnecessary alarmism when melt rates and ice-melt masses are presented without perspective and juxtaposed against claims that scientists are worried. This paper uses the same facts but places them in perspective to show that catastrophic risks do not exist.

The big Arctic Sea-Ice shift of 2007: Ice refuses to melt

by Javier, April 23, 2019 in WUWT


I have maintained since 2015 that in the 2006-2007 season the Arctic underwent a cyclical phase shift, and the rapid sea-ice melting observed over the previous decades ended. A few scientists predicted or explained this shift based on their study of multi-decadal oscillations (see bibliography). They were ignored by mainstream climatology and the press because the “anthropogenic” melting of the Arctic is one of the main selling points of the climate scare. See for example:

Year after year the data supports my view over the desperate scaremongers like Tamino. With the passing of time it is more and more difficult to defend the idea that Arctic melting is continuing, so alarmists keep changing the metric. First it was September sea-ice extent (SIE), then September sea-ice volume, and now annual average SIE. However, the reference measurements are September minimum SIE and March maximum SIE.

This article is more than a biannual update on the Arctic ice situation, as I will focus specifically on showing evidence for the trend change that took place in 2007. As 12 years have passed since the shift, the best way is to compare the 2007-2019 period with the previous 1994-2006 period of equal length to display the striking differences between both periods.

Figure 1. Changes in September SIE for both periods as a percentage change over the first year of the period.

Arctic Ice Gain Embarrasses Global Warming Scientists. 40-Year Meteorologist: “Don’t Be Surprised Over What Happens Next 10 -15 Years!

by P. Gosselin, April 21, 2019 in NoTricksZone


Yesterday I wrote here how some scientists misrepresent the observed data concerning Greenland ice melt in order to get the alarming results they want. There we see that Greenland has been melting, but recently much more slowly than what we are often led to believe.

Looking at the latest Greenland ice volume data from the Danish Meteorological Institute (DMI), we see that currently the ice volume is below normal, but well within the range of the past 17 years:

Data source: Danish Meteorological Institute. Chart by Kirye.

Also Tony Heller at Real Science here plotted Arctic ice volume for the past 12 years in succession. Here’s how all the media-claimed rapid Arctic melting really looks

CO2’s Influence Was 0.006 W/m² Per Decade During The Last Deglaciation. And This Melted Ice Sheets How?

by K. Richard, April 18, 2019 in NoTricksZone


According to the calculations of Dr. James Hansen, the radiative influence derived from the increase in CO2 during the last deglaciation was so negligible that it equated to “a third of energy required to power a honey bee in flight” (Ellis and Palmer, 2016).

 

Image Source: Ellis and Palmer, 2016

We now know how insects and bacteria control ice

by University of Utah, April 14, 2019 in WUWT


Proteins help organisms form or inhibit ice crystals

Contrary to what you may have been taught, water doesn’t always freeze to ice at 32 degrees F (zero degrees C). Knowing, or controlling, at what temperature water will freeze (starting with a process called nucleation) is critically important to answering questions such as whether or not there will be enough snow on the ski slopes or whether or not it will rain tomorrow.

Nature has come up with ways to control the formation of ice, though, and in a paper published today in the Journal of the American Chemical Society University of Utah professor Valeria Molinero and her colleagues show how key proteins produced in bacteria and insects can either promote or inhibit the formation of ice, based on their length and their ability to team up to form large ice-binding surfaces. The results have wide application, particularly in understanding precipitation in clouds.

“We’re now able to predict the temperature at which the bacterium is going to nucleate ice depending on how many ice-nucleating proteins it has,” Molinero says, “and we’re able to predict the temperature at which the antifreeze proteins, which are very small and typically don’t work at very low temperatures, can nucleate ice.”

Less Ice In Arctic Ocean 6000-7000 Years Ago

by Geological Survey of Norway, October 20, 2008 in ScienceDaily


Recent mapping of a number of raised beach ridges on the north coast of Greenland suggests that the ice cover in the Arctic Ocean was greatly reduced some 6000-7000 years ago. The Arctic Ocean may have been periodically ice free.

”The climate in the northern regions has never been milder since the last Ice Age than it was about 6000-7000 years ago. We still don’t know whether the Arctic Ocean was completely ice free, but there was more open water in the area north of Greenland than there is today,” says Astrid Lyså, a geologist and researcher at the Geological Survey of Norway (NGU).

Inconvenient: NASA says a Greenland glacier did an about-face – growing again

by Anthony Watts, March 25, 2019 in WUWT


“…scientists were so shocked to find the change.”

From NASA JPL: Cold Water Currently Slowing Fastest Thinning Greenland Glacier

NASA research shows that Jakobshavn Glacier, which has been Greenland’s fastest-flowing and fastest-thinning glacier for the last 20 years, has made an unexpected about-face. Jakobshavn is now flowing more slowly, thickening, and advancing toward the ocean instead of retreating farther inland. The glacier is still adding to global sea level rise – it continues to lose more ice to the ocean than it gains from snow accumulation – but at a slower rate.

The researchers conclude that the slowdown of this glacier, known in the Greenlandic language as Sermeq Kujalleq, occurred because an ocean current that brings water to the glacier’s ocean face grew much cooler in 2016. Water temperatures in the vicinity of the glacier are now colder than they have been since the mid-1980s.

See also here in NBS

GREENLAND ICE SHEET SIXTH HIGHEST ON RECORD

by GWPF, December 7, 2019


In 2018, Greenland’s total  surface mass budget (SMB) is almost 150bn tonnes above the average for 1981-2010, ranking as sixth highest on record.

 

The Danish Meteorological Institute (DMI) also performs daily simulations of how much ice or water the Ice Sheet loses or accumulates. Based on these simulations, an overall assessment of how the surface mass balance develops across the entire Ice Sheet is obtained (Fig. 4).

At the end of the 2018 season (31 August 2018), the net surface mass balance was 517 Gt, which means that 517 Gt more snow fell than the quantity of snow and ice that melted and ran out into the sea.

Greenland’s Glaciers Expanding Again

by P. Homewood, March 11, 2019 in NotaLotofPeopleKnowThat


As I reported last  September, Greenland’s ice sheet mass balance had grown at close to record levels for the second year running.

To clarify again, the mass balance calculation accounts for:

1) Snowfall

2) Ice melt

3) Ablation

 

In other words, it does not include calving.

http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/#

..

Arctic Sea Ice Extent Same As In 2005

by P. Homewood, March 5, 2019 in NotaLotofPeopleKnowThat


You may wonder why you have not heard much about Arctic sea ice death spirals and Greenland heatwaves this winter.

Hardly surprising, because the Arctic stubbornly refuses to follow the agenda.

Average sea ice extent last month was the highest since 2013, and stands as high as it did in 2005.

http://ocean.dmi.dk/arctic/icecover_30y.uk.php

Strong Arctic sea-ice growth this year

by Andy May / Javier, February 24, 2019 in WUWT


February is not over, and Arctic sea-ice extent is already over half a million square kilometers higher than last year at this day.

The growing season has not ended, and 2019 Arctic sea-ice extent is already higher than the previous four years and six out of the last 14 years.

Figure 1. Arctic sea-ice extent. Note the left edge of the graph is February 1, not January 1.  http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

Arctic sea-ice has stubbornly resisted the very warm years between 2015-2017 caused by the big El Niño. Are we going to see an increase in Arctic sea-ice over the next few years? Only time will tell, but the idea cannot be discarded.