«
Global Sea ice trend by year only (barely) crosses 95 % significance when the first two months of satellite data is included for the entire record.»
Here's
the global sea ice trend, combining what's going on up north and down south.
From 2006 to 2016,
global sea ice trends have also been remarkably stable despite a massive increase in anthropogenic CO2 emissions during this period.
Not exact matches
Too much debate treats temperature (and especially the most recent
global average) as the sole indicator, whereas many other factors are at play including
sea levels, ocean acidity,
ice sheets, ecosystem
trends, and many more.
Researchers are still investigating what forces, including
global warming, are driving Antarctic
sea ice trends.
As a result, the amount of
global sea ice continues a net downward
trend.
«Environmental scientists have been saying for some time that the
global economy is being slowly undermined by environmental
trends of human origin, including shrinking forests, expanding deserts, falling water tables, eroding soils, collapsing fisheries, rising temperatures, melting
ice, rising
seas, and increasingly destructive storms,» 6.
Here are some possible choices — in order of increasing sophistication: * All (or most) scientists agree (the principal Gore argument) * The 20th century is the warmest in 1000 years (the «hockeystick» argument) * Glaciers are melting,
sea ice is shrinking, polar bears are in danger, etc * Correlation — both CO2 and temperature are increasing * Sea levels are rising * Models using both natural and human forcing accurately reproduce the detailed behavior of 20th century global temperature * Modeled and observed PATTERNS of temperature trends («fingerprints») of the past 30 years ag
sea ice is shrinking, polar bears are in danger, etc * Correlation — both CO2 and temperature are increasing *
Sea levels are rising * Models using both natural and human forcing accurately reproduce the detailed behavior of 20th century global temperature * Modeled and observed PATTERNS of temperature trends («fingerprints») of the past 30 years ag
Sea levels are rising * Models using both natural and human forcing accurately reproduce the detailed behavior of 20th century
global temperature * Modeled and observed PATTERNS of temperature
trends («fingerprints») of the past 30 years agree
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.
On Mr. Will's defense of his accuracy, particularly on
trends in
sea ice at both poles as they related to
global warming, it's worth pointing out a few things.
There are certainly better indicators of
global warming
trends —
ice sheet volume,
sea ice extent and
sea surface temperatures all come to mind — but hurricanes get people's attention.
Re 9 wili — I know of a paper suggesting, as I recall, that enhanced «backradiation» (downward radiation reaching the surface emitted by the air / clouds) contributed more to Arctic amplification specifically in the cold part of the year (just to be clear, backradiation should generally increase with any warming (aside from greenhouse feedbacks) and more so with a warming due to an increase in the greenhouse effect (including feedbacks like water vapor and, if positive, clouds, though regional changes in water vapor and clouds can go against the
global trend); otherwise it was always my understanding that the albedo feedback was key (while
sea ice decreases so far have been more a summer phenomenon (when it would be warmer to begin with), the heat capacity of the
sea prevents much temperature response, but there is a greater build up of heat from the albedo feedback, and this is released in the cold part of the year when
ice forms later or would have formed or would have been thicker; the seasonal effect of reduced winter snow cover decreasing at those latitudes which still recieve sunlight in the winter would not be so delayed).
Over all, the analysts as a group see no deviation from the long - term
trend toward thinning and dwindling summer
sea ice given how the Arctic tends to amplify the long - term
global warming
trend.
Vicky Pope, a meteorologist in England's climate and meteorology office, has a remarkable op - ed in the Guardian warning that scientists, the media and campaigners of all stripes who use short - term
trends in weather or
sea ice to make points are misleading the public about
global warming.
Figure 3: National Snow and
Ice Data Center (NSIDC) Antarctic, Arctic, and global (sum of the two) sea ice extents with linear tren
Ice Data Center (NSIDC) Antarctic, Arctic, and
global (sum of the two)
sea ice extents with linear tren
ice extents with linear
trends.
While
sea ice in the Arctic grows and shrinks with the seasons, there is an overall declining
trend, as north pole has warmed roughly twice as fast as the
global average.
Arbetter, 4.7, Statistical A statistical model using regional observations of
sea ice area and
global NCEP air temperature,
sea level pressure, and freezing degree day estimates continues the
trend of projecting below - average summer
sea ice conditions for the Arctic.
Just as importantly, he says, the model helps to explain regional
trends that seem to defy the
global warming hiatus, including record - breaking heat in the United States last year, and the continued decline of Arctic
sea ice.
sea ice, arctic, antarctic, climate change,
global warming, general linear model, dummy variable, regression, deseasonalized
trend,
trend analysis
Keywords: Arctic
sea ice, Antarctic
sea ice, passive microwave imaging,
global warming, climate change, polar
ice caps,
sea ice extent,
sea ice dispersion,
trends, uncertainty in
trends, statistical inference
Over the long - term, melting of the West Antarctic
Ice Sheet could yield as much as 10 to 14 feet of
global average
sea level rise, with local
sea level rise varying considerably depending on land elevation
trends, ocean currents and other factors.
When sceptics look at statistical data, whether it is recent
ice melt, deep
sea temperatures, current
trend in
global surface temperatures, troposphere temperatures,
ice core records etc. they look at the data as it is without any pre-conceptions and describe what it says.
The long - term
trend is for the
sea ice to continue melting due to
global warming, meaning the scramble to access these resources will only intensify.
ocean temperatures, widespread melting of snow and
ice, and rising
global average
sea level,» are three disjoint sources of confirmation that give us reliable enough
trend information to establish consilience about what we may say after 2005 on HadCRUT4.
There has been a long - term downward
trend in summer
global sea ice extent, though the
trend is less clear in the winter, reflecting the fact that the Arctic shows a clearer long - term
trend than the Antarctic.
Much importance has been ascribed to tracking the change in Arctic
sea ice, but what about the
global trend?
However there is some important information that needs to be presented related to the
global trend of
sea ice as measured by satellite since 1979.
If you correct for the discontinuity in the way area is measured, it's undeniable that
global sea ice has
trended down over the time span monitored by satellites.
I'm inclined to think that Ocean Heat Content,
trends in land
ice and
Sea levels are more appropriate indicators of
global climate change than surface air temperatures, but that's another issue.
Or does the background
trend in Figure 3 represent the
global warming «forced» signal of an ever - increasing
sea ice loss, plus natural variability (Bitz)?
The first graph on
global sea ice area uses an expanded scale in an attempt to hide the fact that indeed, there's a declining
trend (caption «no
trend over 30 years»).
Although there is significant season - to - season and year - to - year variability of world
sea -
ice coverage, there is no dramatic
trend in
global sea -
ice loss.
In any event, it would not be surprising to find a slight downward
trend for
sea ice as the late 1970s came at the end of a decades - long period of slight
global cooling.
In fact, it's pretty clear that the end - summer
sea ice extent at one Pole doesn't mean anything WRT
global temperature, especially if there is an opposite
trend at the other Pole.
1 — did the circulation - driven fall in Arctic
sea ice (which AR4 models don't do a great job of) have anything to do with the recent jump in Arctic temperatures and if so, could we get the «right»
global temp
trend for the «wrong» reasons.
Another indicator of intensifying
global warming: The area of Arctic Ocean covered by
sea ice, a major influencer of weather for the Northern Hemisphere, continued its multi-year shrinking
trend.
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?
Global Warming Theory «Completely Disconnected From the Observations» Extensive analysis of temperature
trends in the Arctic reveals that there has been no detectable long - term change since the beginning of the 20th century, and thus predictions of a
sea ice - free Arctic in the coming decades due to dramatically rising temperatures are not rooted in observation.
With virtually all CAGW projections diverging further from reality, CAGW's survival depends on propagandizing lies and half - truths: the «97 %» meme, severe weather,
sea levels,
global warming
trends, ocean acidification, polar bear and penguin populations, polar
ice caps, etc., are all supposedly worsening at «unprecedented» rates.
In fact, the
sea ice gains in Antarctica have perhaps modestly superseded the losses in the Arctic, resulting in a very slight increasing overall
trend in
global - scale
sea ice during the last 10 years:
The Antarctic
sea ice extent has been slowly increasing contrary to expected
trends due to
global warming and results from coupled climate models...
Following the
trend in
global modelling, RCMs are increasingly coupled interactively with other components of the climate system, such as regional ocean and
sea ice (e.g., Bailey and Lynch 2000; Döscher et al., 2002; Rinke et al., 2003; Bailey et al., 2004; Meier et al., 2004; Sasaki et al., 2006a), hydrology, and with interactive vegetation (Gao and Yu, 1998; Xue et al., 2000).
The G refers to
global, thus the MEAN
global T must rise, the mean
sea ice extent must decrease,
global sea level
trend must increase,
global tornadoes must rise,
global floods must increase, the rate of
global sea riseust rise, and all the
global change MUST be catastrophic, and clearly outside of recent past
global flux.
For both hemispheres combined, then, the addition of about 65 ppm of atmospheric CO2 concentration since 1979 has apparently had no overall effect on
global - scale
sea ice trends.
In its latest post the site looks at the July results and the overall
global temperature and
sea ice trend.
«Climate scientists have cracked the mystery of why Antarctic
sea ice has managed to grow despite
global warming — but the results suggest the
trend may rapidly reverse, a new study says.»
The loss of
sea ice also has the potential to accelerate
global warming
trends and to change climate patterns.
For example, additional evidence of a warming
trend can be found in the dramatic decrease in the extent of Arctic
sea ice at its summer minimum (which occurs in September), decrease in spring snow cover in the Northern Hemisphere, increases in the
global average upper ocean (upper 700 m or 2300 feet) heat content (shown relative to the 1955 — 2006 average), and in
sea - level rise.
With these
trends in
ice cover and
sea level only expected to continue and likely worsen if atmospheric carbon dioxide levels continue to rise, they could alter the stresses and forces fighting for balance in the ground under our feet — changes that are well - documented in studies of past climate change, but which are just beginning to be studied as possible consequences of the current state of
global warming.
In a February report, Dr. Parkinson said, «If
trends toward shortened
sea ice seasons and lesser
sea ice coverage continue, this could entail major consequences to the polar and perhaps
global climate, and to the lifestyles and survivability of selected Arctic plant and animal species.»