2011 was the...

9th warmest year of the recorded period, from 1880 till now. This is according to NASA who have apparently finished calculating their data. It is also the 9th warmest year in the past 10 which has now seen 9 of the top 10 warmest years on record. This is what we should expect to see if the climate was in fact warming, every year won't be the warmest but decades on a whole should be getting warmer. In fact this is true, the 00s were warmer than the 90s the 90s warmer than the 80s, something is clearly happening you have to be openly trying to ignore the data not to see that. The image below is from NASA and shows the yearly temperature average since 1880, I have also included a little blurb from the same article below but I recommend you read the whole thing.

From NASA:

The global average surface temperature in 2011 was the ninth warmest since 1880, according to NASA scientists. The finding continues a trend in which nine of the 10 warmest years in the modern meteorological record have occurred since the year 2000.

NASA's Goddard Institute for Space Studies (GISS) in New York, which monitors global surface temperatures on an ongoing basis, released an updated analysis that shows temperatures around the globe in 2011 compared to the average global temperature from the mid-20th century. The comparison shows how Earth continues to experience warmer temperatures than several decades ago. The average temperature around the globe in 2011 was 0.92 degrees F (0.51 C) warmer than the mid-20th century baseline.

We know the planet is absorbing more energy than it is emitting," said GISS Director James E. Hansen. "So we are continuing to see a trend toward higher temperatures. Even with the cooling effects of a strong La Niña influence and low solar activity for the past several years, 2011 was one of the 10 warmest years on record."

The difference between 2011 and the warmest year in the GISS record (2010) is 0.22 degrees F (0.12 C). This underscores the emphasis scientists put on the long-term trend of global temperature rise. Because of the large natural variability of climate, scientists do not expect temperatures to rise consistently year after year. However, they do expect a continuing temperature rise over decades.

The first 11 years of the 21st century experienced notably higher temperatures compared to the middle and late 20th century, Hansen said. The only year from the 20th century in the top 10 warmest years on record is 1998.

A Single Data Point!

Every winter it seems that the climate denialists bring out the but it's cold argument and while I have covered it before (see here, here, and here) I wanted to point out why it is not a valid argument against global climate change. I was inspired to do this based on a recent post over at Conservapedia which said the following [source]:

Global Warming Update: Cooling Trend Continues. March 2011 is on record as the coldest in 15 years. [14]

I saw that post and said, "so?" but I realized that many people who read Conservapedia, then again I doubt many people who read Conservapedia read my blog, might not realize that one month being colder isn't important.

The problem with one cold month is that it is only one data point. Global climate change is based on a build up of data that spans decades of research. One or two colder than normal months out of decades do not influence the data to a great degree nor should they be considered proof of the end of climate change, these are what are typically referred to as weather. What Conservapedia and the climate change denialists are doing are cherry picking data. I can do the same thing, as a resident of Lubbock, TX I know last month was hot in fact there was a least one day that we set a new record high. What is more is that the National Weather Service agrees with me and therefore that link that conservapedia posted is completely wrong March was one of the top 15 warmest months on record for the area and therefore their view that global warming is not happening is wrong, and the fact that Texas is in a severe drought means that the whole state is going to run out of water forever (sorry I wanted to find a way to get that link in a post somewhere).

It doesn't work that way, in fact even 2010 being tied for the warmest on record isn't, by itself, important. What is important is the long term trends like the graph to the left which shows over the long term the temperatures have been increasing globally, from Wikipedia. If you go to NASA's climate change website you can see all of the data accumulated thus far showing that climate change is in fact happening. Climate scientists might even actually expect 2011 to be much cooler than 2010 (I don't know that they do this was more just an example), but this will not pronounce climate change dead but will in fact just say that temperatures will vary year to year in the same way that temperature varies day to day. These individual variations are not important again it will always be colder in January than in July in the northern hemisphere and some places will always see snow. What is important is the long term trend, this is what scientists are interested in and this is what they look at. As summarized here, yes I know it is Wikipedia but the summary is good, you can see that of the 20 warmest years the vast majority in the upper half are in the last decade, and here you can see that the last 3 decades have been the warmest decades with each being warmer than the last. That sort of information is important and how climate change is decided not, well it was cold today we should stop worrying.