A Condensed Look at ?Arctic Sea Ice Decline: Faster Than Forecast??
7 May, 2007 12:31 pm
A new study indicates that the Arctic Ocean is losing its sea ice cover faster than is captured by the most advanced models used in the 2007 report by the Intergovernmental Panel on Climate Change (IPCC).
The authors compared the last fifty years of sea ice observations with output from the eighteen IPCC climate models, and found that none of the models captured the observed trend during September (the end of the summer melt season) of -7.8 percent per decade. On average, the models suggest a trend that is three times smaller, at –2.5 percent per decade. The fastest rate of September retreat in any individual model simulation was -5.4 percent per decade, which is still thirty percent slower than scientists observed.
Currently, the observations indicate sea ice conditions for September are about thirty years ahead of where the models say we should be. Thus, it is entirely likely that a seasonally ice-free Arctic state may well occur during the first half of this century.
Stroeve and her co-authors speculate that the computer models may fail to capture the full impact of increased carbon dioxide and other greenhouse gases in the atmosphere. Results from this study suggest about half of the ice loss from 1979 to 2006 is caused by human activities (e.g. greenhouse gases) and the other half is caused by natural variability in the climate system. However, if the models are under-representing the human-induced climate response, greenhouse gases may be playing a significantly greater role.
The discrepancy between the models and the observations is not necessarily an indication of poor models, but rather is an indication of the complexity of change in the Arctic, and the difficulty of accurately modeling such change. Although the models used in the IPCC report incorporate many improvements compared to earlier climate models, shortcomings remain, such as the models ability to accurately model the vertical structure in the ocean and oceanic heat transport. Recent studies indicate that the transport of heat from the sub-polar oceans to the Arctic waters is playing a larger role than previously thought in melting the sea ice. This contribution to melting of the Arctic ice pack is underestimated in our current models.
Although it remains a mystery as to the exact date when the Arctic may become ice free in summer and how rapid this transition may be, this new state would have profound implications for climate around the globe. The snow and ice at the poles help keep our planet cool by reflecting most of the incoming solar energy from the sun back out to space. As the amount of snow and ice decreases, the Earth’s surface absorbs more solar energy, furthering snow and ice melt and resulting in more warming. A warmer Arctic will result in altered atmospheric and oceanic circulations that will affect weather worldwide. Studies have already linked Arctic sea ice loss to changes in atmospheric patterns that cause reduced rainfall in the American West and increased precipitation over western and southern Europe.
Already, the loss of sea ice has had adverse effects for the people and wildlife in the Arctic that depend on the sea ice for their livelihood. The complete disappearance of the summertime sea ice will leave the polar bear, ring seals and other Arctic creatures without habitat, and will have a profound impact on the people who live in the Arctic.
Reference:
Stroeve, J., et al. (2007), Arctic sea ice decline: Faster than forecast, Geophys. Res. Lett., 34, L09501, doi:10.1029/2007GL029703.
"Average Arctic temperatures increased at almost twice the global average rate in the past 100 years. Arctic temperatures have high decadal variability, and a warm period was also observed from 1925 to 1945."
Actually this IPCC statement is extreme superficial, because the the period from 1918 to 1922 displays exceptionally rapid winter warming, see: I.V.Polyakov, et.al.; Variability of the Intermediate Atlantic Water of the Arctic Ocean over the last 100 Years, Journal of Climate, Vol.17, No.23, 2004.
While Polyakov gets its right with the timing, his explanation of the causation seems insufficient., unfortunatly IPCC is ignoring this basic fact completely.
[Response] First off, I assume the "burning question" is what is the cause and how might it be different than the warming in the 1920s-19402. Though it doesn't address the sea ice directly, the IPCC Summary for Policy Makers clearly states that anthropogenic forcing is behind the recent warming. The Summary for Policy Makers is meant to be an overview, so it's succinct. You can access the full report here: http://www.ipcc.ch/. The statement quoted in the post is in the SPM references Chapter 3, Section 2, which is a pretty detailed discussion of temperatures. More information is also found in Chapter 4, the Technical Summary, and the FAQ. Realize that details of the earlier warming are not well known owing to the sparse data record and conclusions drawn from different studies are NOT entirely consistent with each other. Some of the analysis (e.g. by Jones et al., 2003) indicate the 1930s warming occured predominantly in spring over the North Atlantic and in northwestern Canada. Other analysis by Overland et al. (2004) show warming centered on 1940 during winter over a broad area, excluding the North Pacific sector. Polyakov et al. (2002) argue that the more notable feature of the Arctic is its prnounced low-frequency variability and that this variability is probably under-sampled in the short data record. I think what's important here though is that the recent warming is very different than that in the 1920s-1940s in that it appears in essentially all latitudes now (e.g. it's global and not simply confined to the Arctic). And although the warming is present for the entire Northern Hemipshere in this recent warming, it does become more strongly expressed as latitude increases.
Weather it?s call Global Warming or Climate Change, most of mankind now believes that something is changing the Planet?s weather. In the hours directly following 9-11, scientists claim there was a measurable positive impact on the planets atmosphere. They contributed it to the fact that the airline industry had been grounded. But did anyone really consider the fact that the cellular telephone industry had also been turned off?
Over the last 20 years there has been a technological explosion in the cellular and wireless technology industry. More radio and microwaves are be transmitted through our atmosphere every single hour of every day than every before. In fact in an urban area we have seen it grow from using 40 frequencies to using over 16000 frequencies in the same area. This industry has grown by more than 400 times its size over 20 years.
It takes 200 watts of microwave energy three minutes to boil a cup of water. It takes 4 watts of microwaves to transmit one cell phone frequency between towers. It takes four of these frequencies to make one cellular telephone call work. In comparison 13 three minutes cellular telephone calls puts enough energy to boil water directly into the atmosphere. It is a known scientific fact that these waves cause water molecules to vibrate faster, and faster vibrating molecules only get hotter. These same waves can also go through solid objects and are known to shake them apart. We use them to do this in medical treatments every day. They could also be causing ice to breakup and melt faster then ever before because they are working from the inside out.
It takes a lot of energy to change a cup of water to vapor, but it takes considerably less energy to keep water vapor molecules in the atmosphere from condensing into rain. If it is kept vaporized it will not fall out of the sky, and more water vapor will build up over time. When conditions are right to cause this water vapor to condense and fall out of the sky you can bet there will be a lot more of it just like we are seeing in the world?s weather today. Rain is one of the ways Carbon gets removed from the atmosphere. A buildup of Carbon in atmosphere may actually be a way to measure the over use of Microwaves in the atmosphere.
The growth of this Wave Technology can be directly related to the increase in the planets temperature. The more we use the hotter it is getting. Along with this growth so has the rate of skin cancer grown. The worlds Honey Bees are also in trouble, it is believed that wave technologies are causing them to becoming confused and loose their way back too their hives. Wave Technology has become the new Tobacco Industry of today, to hell with public health, so long as it can make a quick profit. When the River Thames recently spilled over its banks it caused 40 Billion dollars in flood damage, how was this profitable for anyone.
All the hype around the Carbon Factor as being the leading cause of weather change may actually be a marketing strategy for existing industries. By creating a reason to change industries can stimulate growth and generate new wealth. By turning it into a crisis industry can also hope to cash in at the big cash cow - Government.
Planet Earth has always had to deal with the Carbon factor and over millions of years has developed ways to protect itself against its impact. But this much wave technology is new to the planet and maybe it had a tipping point in the atmosphere too. I believe that wave technology is a major contributing cause to global warming, and if we hope to help the planet we must consider the truth about this convenience and turn it off.