Global climate model projections for sea
ice trends around Antarctica are at odds with what is being observed.
Scientists who study the warming seas and complicated climate and
ice trends around Antarctica got a big jolt in recent days as yet another great fringing, floating ice shelf jutting from the Antarctic Peninsula began to disintegrate.
Not exact matches
It is one of the reasons ascribed to the increasing
trend in sea
ice around Antarctica.
Large - scale surface temperature reconstructions yield a generally consistent picture of temperature
trends during the preceding millennium, including relatively warm conditions centered
around A.D. 1000 (identified by some as the «Medieval Warm Period») and a relatively cold period (or «Little
Ice Age») centered
around 1700.
Changes in the winds
around Antarctica therefore change
ice - concentration
trends around Antarctica [8] by influencing sea -
ice production and melt rates [9].
Extrapolating based on date from 1980 to the present yields and estimate
around the 2040 for zero September
ice volume while using an apparent steeper
trend since 2000 yields an estimate
around 2015 for the lower curve in fig. 1 or
around 2020 using the upper curve as a guide.
It was when the
ice extent
trend was pointing steeply downwards in early Sep that I was the only one on North Pole Notes to argue it would turn
around quickly (you're implying to people that I was instead talking about pre-season projections.)
To get a sense of how the views of Arctic experts have coalesced
around a rising human influence on the region's climate, you can scan previous stories from 2001, 2005, and 2007 on
ice trends and possible causes.
The net
trend in the past decennia is a cooling of the (deeper) Atlantic
around South Greenland, which points to more cooler water /
ice export from the Arctic.
In fact, as I proposed in my overview of
ice trends last October, the system up there may be becoming more like the sea
ice around Antarctica, which flashes into existence each austral winter and then all disappears each southern summer.
Ice depth
trends around Antarctica?
But all of the 15 teams offering projections say
ice extent will remain well below the average for the last quarter century and a downward
trend in summer
ice around the North Pole has not abated.
But, he also says: «teams offering projections say
ice extent will remain well below the average for the last quarter century and a downward
trend in summer
ice around the North Pole has not abated,» and we readers are then linked to his October, 2007 article and an August, 2007 image of a «warmed over» Artic.
The goal, the scientists say, is to compare independent methods of gauging
ice trends from factors including sea temperature,
ice thickness and cycles of atmospheric pressure and winds
around the Arctic.
Study of Greenland
ice provides a 2500 year perspective indicating we headed into a mini-
ice-age as happened from the mid 1300's to the mid 1800's; and the data from the 1200 or so floating buoys
around the world's oceans are likewise showing a cooling
trend, and have been for some time.
But on the contrary, the Southern Ocean has warmed by
around 0.5 °C in the three decades since satellites began measuring sea
ice trends.
«The Earth has been in a warming
trend since the depth of the Little
Ice Age
around 1680.
What is known is that during the period called Little
Ice Age, global glacial were advancing, and starting
around 1850, instead advancing global glacier became retreating, this
trend of glacial retreat continues to the present time, but not all glaciers adding during the Little
Ice Age have not yet melted.
This is an important article, Climategrog, because it shows from a different type of data (date of minimum extent) that something happened
around 2007 to Arctic sea
ice that interrupted a 35 year
trend.
Large - scale surface temperature reconstructions yield a generally consistent picture of temperature
trends during the preceding millennium, including relatively warm conditions centered
around A.D. 1000 (identified by some as the «Medieval Warm Period») and a relatively cold period (or «Little
Ice Age») centered
around 1700.
The pattern of temperatures shows a rise as the world emerged from the last deglaciation, warm conditions until the middle of the Holocene, and a cooling
trend over the next 5000 years that culminated
around 200 years ago in the Little
Ice Age.
Jonathan Bamber, director of the Bristol Glaciology Centre at the University of Bristol, UK, says: «We have already seen an unusually early start to melting
around the margins of Greenland in 2016 and the new findings from NSIDC of exceptionally low sea
ice extent for May and the lowest Northern Hemisphere snow cover in April for 50 years is in line with the longer - term, decadal
trends for the Arctic as a whole,» said
Maybe you even see this with the
trends around the
Ice Ages?
The oceans have risen by
around 2.5 cm over the last decade, emphasising just how warm the seas and the atmosphere have become already As
ice caps glaciers and sea
ice show us the
trend in rather obvious ways, scientists studying the phenomena have been shocked.
The modeled evolution of Arctic sea
ice volume appears to be much stronger correlated with changes in
ice thickness than with
ice extent as it shows a similar negative
trend beginning
around the mid-1990s.
The composite record show large sea
ice variations
around a small negative
trend since 1900, although the
trend from a statistical point of view is not significant (Polyakov et al. 2003).
If the sea
ice around Antarctica is growing (on a decadal
trend basis)-- which any schoolboy analysis of freely available basic data shows...... what does this tell you about the certainty of global warming?
From 1978 to 1996, the average
ice cover
around Antarctica showed almost no
trend (a slight increase 1.3 % per decade), however
ice decreased by 2.9 % per decade on average over the arctic seas (1).
The
ice around the Antarctic has had a reverse
trend as is actually covering a bigger area this year than in 1979.
The 30 % concentration graph, the DMi graph, one that is weightier than the 15 % because it shows what is happening at the heart of the Arctic, and not just what is happening (for the moment)
around the circumference of the
ice, shows a rapid, and strong (even surprising for how strong it is this year) growing
trend in Arctic
ice since 2007.