Arguments
Evidence for global warming
What the science says...
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There are many lines of evidence indicating global warming is unequivocal. |
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Climate Myth...
It's not happening
"...these global warming studies that now we're seeing (are) a bunch of snake oil science." (Sarah Palin)
The 2009 State of the Climate report of the US National Oceanic and Atmospheric Administration (NOAA), released in mid-2010, brings together many different series of data “from the top of the atmosphere to the depths of the ocean”. The conclusion? All of these independent lines of evidence tell us unequivocally that the Earth is warming.
The very accessible 10-page summary examines the trends for 10 key climate indicators using a total of 47 different sets of data. All of the indicators expected to increase in a warming world, are in fact increasing, and all that are expected to decrease, are decreasing:
The 10 indicators are:
- Land surface air temperature as measured by weather stations. You know all those skeptic arguments about how the temperature record is biased by the urban heat island effect, badly-sited weather stations, dropped stations, and so on? This is the only indicator which suffers from all those problems. So if you’re arguing with somebody who tries to frame the discussion as being about land surface air temperature, just remind them about the other nine indicators.
- Sea surface temperature. As with land temperatures, the longest record goes back to 1850 and the last decade is warmest.
- Air temperature over the oceans.
- Lower troposphere temperature as measured by satellites for around 50 years. By any of these measures, the 2000s was the warmest decade and each of the last three decades has been much warmer than the previous one.
- Ocean heat content, for which records go back over half a century. More than 90% of the extra heat from global warming is going into the oceans – contributing to a rise in…
- Sea level. Tide gauge records go back to 1870, and sea level has risen at an accelerating rate.
- Specific humidity, which has risen in tandem with temperatures.
- Glaciers. 2009 was the 19th consecutive year in which there was a net loss of ice from glaciers worldwide.
- Northern Hemisphere snow cover, which has also decreased in recent decades.
- Perhaps the most dramatic change of all has been in Arctic sea ice. Satellite measurements are available back to 1979 and reliable shipping records back to 1953. September sea ice extent has shrunk by 35% since 1979.
Science isn’t like a house of cards, in that removing one line of evidence (eg. land surface air temperature) wouldn’t cause the whole edifice of anthropogenic global warming to collapse. Rather, “land surface warming” is one of more than ten bricks supporting “global warming”; and with global warming established, there is a whole other set of bricks supporting “anthropogenic global warming”. To undermine these conclusions, you’d need to remove most or all of the bricks supporting them – but as the evidence continues to pile up, that is becoming less and less likely.
Basic rebuttal written by James Wight
Update July 2015:
Here is a related lecture-video from Denial101x - Making Sense of Climate Science Denial
Last updated on 7 July 2015 by MichaelK. View Archives
On the comment stream at Alex Knapp's Forbes blog:
Daniel Fisher (Forbes staff): "I am not sure the debate is over whether the climate is warming – obviously it has been getting warmer since the last Ice Age, which was a very short time ago. The question is whether that increase is accelerating in a non-random way, and the acceleration is caused by the measured increase in atmospheric CO2. Does this new method help unravel that?"
Bob Tisdale: "That would be difficult to show for a couple of reasons. First, the hypothesis of manmade global warming is only supported by general circulation models, which are known to be imperfect representations of the Earth’s climate systems. Second, that hypothesis is not supported by NOAA’s satellite-era sea surface temperature data or by NOAA’s ocean heat content data since 1955."
Is Tisdale paid?
I think this answer ought to be updated with the more detailed graphic over here:
http://www.skepticalscience.com/graphics.php?g=8
59F tomorrow for Buffalo. 15F above the daily average. Should they now think that temperatures have risen >10 times faster than IPCC thinks? Fact is, winter is coming, and it gets cold and snows a lot in Buffalo in the winter almost every year. Sometimes it gets warm again.
Ironically, though, the large amounts of lake effect snow have been linked to the warming of the lake, resulting in more evaporation, convective lift and, therefore, snow than previously seen. It interacted with a large actic air mass, of the sort we've been seeing that last few years. That pattern has also been attributed to global warming, though the jury is still out.
I would like it very much is this type of article, or at least this one in specific, were updated with the latest numbers. In this new age of Trumpism, we need the best ammo available, please.
Dennis, NOAA maintain a "State of Climate". For global view, updated Oct 2016, see https://www.ncdc.noaa.gov/sotc/global/201610
I like that you devide and explain each indicator clearly. Every evidences are really make sense follow your claim, but I just wondering how can it happen because the weather is become really hot nowadays and seems going to be hotter and hotter? Also ice ages are become smaller than what it was. How can the result be the opposite with the indicators? Is it because of there areb still many factors going on?
Thank you XD