Al Gore told a German audience in December of 2008 that the polar ice cap will disappear in FIVE YEARS.1 A Washington Post story from April of this year says
The data on this winter’s ice buildup came on the day that international ministers gathered in Washington to address issues facing Earth’s polar regions, which have been disproportionately affected by global warming. 2
It goes on to quote Norway’s foreign minister that “The ice is melting…We should all be worried.”
Well, Al Gore, the Washington Post, and Norway’s foreign minister should all be breathing a sigh of relief. As all climatologists agree, the poles should be most affected by global warming, and guess what’s happening at the South Pole? The ice just keeps growing!
Marco Tedesco and Andrew Monaghan just published the latest results on the amount of ice melt in Antarctica, and the results are quite stunning: 3
An “Ice Melt Anomaly” of zero would mean that the amount of ice that melted had not changed from the overall average. Positive values mean that more ice than usual melted, while negative values mean less ice than usual melted.
What trend do you see in the data? The amount of ice that has been melting in the Antarctic has been steadily decreasing for 30 years. Thus, while the Northern Hemisphere (the Arctic) has lost ice over the past 30 years, the Southern Hemisphere (the Antarctic) has gained ice. If the Arctic were losing ice because of “global warming, ” why is the Antarctic gaining ice?
Remember, as every climatologist agrees, the poles should be most affected by any “global warming” that occurs. Thus, if global warming is happening, BOTH the Arctic and the Antarctic should be losing ice quickly. The fact that one is losing ice and the other is gaining it points strongly against the idea that “global warming” is happening.
REFERENCES
1. http://www.youtube.com/watch?v=KrPCUWWjh0c&feature=player_embedded
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2. “New Data Show Rapid Arctic Ice Decline,” Juliet Eilperin and Mary Beth Sheridan, Washington Post, Tuesday, April 7, 2009
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3. Tedesco M. and A. J. Monaghan, “An updated Antarctic melt record through 2009 and its linkages to high-latitude and tropical climate variability,” Geophysical Research Letters, 36 L18502, doi:10.1029/2009GL039186, 2009
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I know that there’s some variation between the energy intake of the two hemispheres, due mostly to the fact that the orbit is non-circular (that is it absorbs more energy but also moves faster at the closer end.) But I thought the Southern Hem got a tad more energy than the North so WHY??? would things be this way around?
The short answer is that we do not know enough about climate to answer the “why” part. You are correct that the Southern Hemisphere gets more energy from the sun, as the earth is slightly closer to the sun during the Southern Hemisphere’s summer. However, the Northern Hemisphere has more land mass, which tends to warm the area more than water does. On average, then, the Southern Hemisphere’s summers are not noticeably warmer than the Northern Hemisphere’s summers.
There are two general ideas out there:
1. The warming we see in the Northern Hemisphere has nothing (or almost nothing) to do with greenhouse gases. Instead, it is the result of a change in the way land is used or a change in the sun. The hemisphere with more land mass will more more sensitive to such things, so that is why the Northern Hemisphere is warming.
2. The cooling in the Southern Hemisphere is due to ozone depletion. Ozone is a greenhouse gas. Thus, ozone depletion will tend to cool the area in which the majority of the depletion takes place. Antarctica is where the vast majority of ozone depletion takes place, because that’s where the strong polar vortex exists, which lifts CFCs and other ozone-destroyers up to the stratosphere.
If my choice is between one of those two views, I choose #1. The problem with #2 is that the ozone layer is in the stratosphere, and that has little effect on the weather or the temperature of the troposphere, which is what is supposedly heating up due to greenhouse gases. Also, ozone-destroying chemicals have been mostly banned for well over 10 years, and there are signs that the “ozone hole” it getting smaller as a result. Nevertheless, the cooling of Antarctica continues.
My gut feeling is that the real answer is neither of those, however.
Just out of interest, how do they measure greenhouse-gasiness? I was just wondering if it’s just reflectivity, in which case must they all work in the same way? For example water (reportedly a more potent greenhouse gas and far more abundant than COtwo) might actually reflect the inbound suns energy rather than serve as a “blanket”? Not that an “air blanket” actually makes much sense, with blankets being useful as convection reducers.
The measurement of greenhouse gases is generally direct. For example, the Mauna Loa Observatory in Hawaii takes air samples and runs them through an infrared spectrometer. Because carbon dioxide is a greenhouse gas, it absorbs infrared light. The pattern of wavelengths absorbed by carbon dioxide is unique to carbon dioxide, so they look at that pattern of wavelengths. The more infrared light absorbed, the more carbon dioxide there is.
Each greenhouse gas has its characteristic absorption pattern in the infrared, so the amount of each greenhouse gas can be tested separately. Interestingly enough, while the amount of carbon dioxide in the atmosphere continues to rise, the amount of methane (a more potent greenhouse gas) has leveled off and has been rather constant for about 10 years now.
Hence it is actually a question of absorbing light rather than of reflecting it as is generally explained? I was trying to ask how they measure how potent a given greenhouse gas is rather than how much there is, but it doesn’t really matter now.
Global warming is about ABSORBING infrared light. The earth radiates infrared light, and the greenhouse gases absorb it, which warms the atmosphere. Aerosols and other chemical that reflect light actually cool the planet, since they reflect the sun’s light before it reaches earth.
There are different ways the strength of a greenhouse gas is measured. You can do it by measuring how much infrared light a given amount of the gas absorbs, for example. However, that doesn’t always reflect “real life” conditions, because the other gases in the atmosphere affect the greenhouse gases, as does the actual vertical distribution of the greenhouse gases. Thus, mathematical models are also used to get an idea of how “powerful” a greenhouse gas is.
Thank you. That makes a lot of sense.