The point is that, objectively speaking, based on actual data, not model data or nursery stories,
the total global sea ice coverage is currently above average.
Overall
total global sea ice has been rising robustly over the past four years.
I have to add that another graph has been making the rounds, showing
the total global sea ice extent.
Not exact matches
Since 1995, researchers found that Greenland has lost a
total of about 4,000 gigatons of
ice, which has become the biggest single contributor to the rise in
global sea levels.
The Greenland
ice sheet is thought to be one of the largest contributors to
global sea level rise over the past 20 years, accounting for 0.5 millimeters of the current
total of 3.2 millimeters of
sea level rise per year.
The Greenland
ice sheet (GIS) has been melting so slowly and so negligibly in recent decades that the entire
ice sheet's
total contribution to
global sea level rise was a mere 0.39 of a centimeter (0.17 to 0.61 cm) between 1993 and 2010 (Leeson et al, 2017).
Pine Island Glacier could collapse — stagnate and retreat far up into the bay, resulting in rapid
sea level rise — within the next few centuries, raising
global sea levels by 1.5 m11, 12, out of a
total of 3.3 m from the entire West Antarctic
Ice Sheet13.
The most exciting thing is we'll get a chance to see the relative strength of all of these over the next few years, and it will most interesting to compare the
total decade of 2010 - 2019 to previous decades in terms of the trends in Arctic
Sea ice,
Global Temps, and of course, OHC.
The
total 2000 — 2008 mass loss of ~ 1500 gigatons, equivalent to 0.46 millimeters per year of
global sea level rise, is equally split between surface processes (runoff and precipitation) and
ice dynamics.
Having said that, it is a really small effect — if the entire Arctic summer
sea ice pack melted (average thickness 2 metres, density ~ 920 kg / m3, area 3 × 10 ^ 6 km ^ 2 (0.8 %
total ocean area) = > a 4.5 cm rise instantly which implies a
global sea level rise of 0.36 mm.
Interesting you cut - off
total ice extents at 2012, especially since the
total extent of Arctic
sea ice has actually increased since then, and in fact the Antarctic
ice extents are at a RECORD MAXIMUM — so things aren't always what they appear to be in a very complex system known as
global climate.
As the rate of
ice loss has accelerated, its contribution to
global sea level rise has increased from a little more than half of the
total increase from 1993 - 2008 to 75 - 80 percent of the
total increase between 2003 - 2007.
Jim, you might consider whether or not
total sea ice is a good indicator of the relationship between CO2 and
global temperature.
And the
global total amount of
sea ice is above normal.
Total global snow /
ice / albedo effects of course encompass far more than the Arctic
sea.
Kjær, Kjeldsen and Korsgaard's team shows that the
ice sheet «contributed substantially to
sea level rise throughout the 20th century, providing at least 25 ± 9.4 millimeters of the
total global mean rise,» writes Csatho, an associate professor of geology in UB's College of Arts and Sciences, in her News and Views analysis.
In combination with the low Arctic
sea ice extent for November, this produced a remarkably low
global sea ice total.
The Greenland
ice sheet (GIS) has been melting so slowly and so negligibly in recent decades that the entire
ice sheet's
total contribution to
global sea level rise was a mere 0.39 of a centimeter (0.17 to 0.61 cm) between 1993 and 2010 (Leeson et al, 2017).
All of these characteristics (except for the ocean temperature) have been used in SAR and TAR IPCC (Houghton et al. 1996; 2001) reports for model - data inter-comparison: we considered as tolerable the following intervals for the annual means of the following climate characteristics which encompass corresponding empirical estimates:
global SAT 13.1 — 14.1 °C (Jones et al. 1999); area of
sea ice in the Northern Hemisphere 6 — 14 mil km2 and in the Southern Hemisphere 6 — 18 mil km2 (Cavalieri et al. 2003);
total precipitation rate 2.45 — 3.05 mm / day (Legates 1995); maximum Atlantic northward heat transport 0.5 — 1.5 PW (Ganachaud and Wunsch 2003); maximum of North Atlantic meridional overturning stream function 15 — 25 Sv (Talley et al. 2003), volume averaged ocean temperature 3 — 5 °C (Levitus 1982).
The melting contributes to about 1 % of the
global sea level rise — a small contribution and only 3 — 4 % of the
total contribution from
global glaciers and
ice caps.
The
total global ice mass lost from Greenland, Antarctica and Earth's glaciers and
ice caps during the study period was about 4.3 trillion tons (1,000 cubic miles), adding about 0.5 inches (12 millimeters) to
global sea level.
RE: 4th Error -RCB- Poses an objection to the non-scientific term catastrophic [NOTE: Scientific «consensus» is often being used & / or implied in standard climate - change discourse - Yet Consensus is a Political Term - NOT a Scientific Term]- HOWEVER - When Jim Hansen, the IPCC & Al Gore, et - al - go from predicting 450 — 500 ppm CO2 to 800 — 1000ppm by the end of the 21st century -LCB- said to the be highest atmospheric CO2 content in 20 — 30 Million YRS -RCB-; — & estimates for aver
global temps by 21st century's end go from 2 * C to 6 * C to 10 * C; — & increased
sea level estimates go from 10 - 20 cm to 50 - 60 cm to 1M — 2M -LCB- which would totally submerge the Maldives & partially so Bangladesh -RCB-; — predictions of the
total melting of the Himalayan
Ice caps by 2050, near total melting of Greenland's ice sheet & partial melting of Antarctica's ice sheet before the 21st century's end; — massive crop failures; — more intense & frequent hurricane -LCB- ala Katrina -RCB- for much longer seasonal durations, etc, etc, etc... — IMO That's Sounds pretty damned CATASTROPHIC to
Ice caps by 2050, near
total melting of Greenland's
ice sheet & partial melting of Antarctica's ice sheet before the 21st century's end; — massive crop failures; — more intense & frequent hurricane -LCB- ala Katrina -RCB- for much longer seasonal durations, etc, etc, etc... — IMO That's Sounds pretty damned CATASTROPHIC to
ice sheet & partial melting of Antarctica's
ice sheet before the 21st century's end; — massive crop failures; — more intense & frequent hurricane -LCB- ala Katrina -RCB- for much longer seasonal durations, etc, etc, etc... — IMO That's Sounds pretty damned CATASTROPHIC to
ice sheet before the 21st century's end; — massive crop failures; — more intense & frequent hurricane -LCB- ala Katrina -RCB- for much longer seasonal durations, etc, etc, etc... — IMO That's Sounds pretty damned CATASTROPHIC to ME!
Current
total ice - loss in Greenland is running at an estimated 200 Gte / yr and Antarctica at 150 Gte / yr (with
ice mass gain in the east and loss in the west — with some estimates of a net gain)-- at that rate of 1mm / yr, by 2100 the
global ice - loss would raise
sea level by a little over 3 inches.
Arctic and
global sea ice totals have moved consistently downward over 38 years.
But one modeling study put the threshold level for the eventual near - complete loss of Greenland's
ice sheet at a local warming of just 2.7 C — which, due to Arctic amplification, means a
global warming of only 1.2 C.
Total melting of Greenland — luckily, something that would likely take centuries — would raise
sea levels by 7 meters, submerging Miami and most of Manhattan, as well as large chunks of London, Shanghai, Bangkok and Mumbai.