Hottest Year in U.S. of the Past 34 Years; Ninth Hottest Globally

Every month University of Alabama in Huntsville climatologists John Christy and Roy Spencer report the latest global temperature trends from satellite data. In their year-end roundup, Christy notes that 2012...

...was the warmest year on record for both the contiguous 48 U.S. states and for the continental U.S., including Alaska. For the U.S., 2012 started with one of the three warmest Januaries in the 34-year record, saw a record-setting March heat wave, and stayed warm enough for the rest of the year to set a record.

Compared to seasonal norms, March 2012 was the warmest month on record in the 48 contiguous U.S. states. Temperatures over the U.S. averaged 2.82 C (almost 5.1° Fahrenheit) warmer than normal in March; the warmest spot on the globe that month was in northern Iowa. The annual average temperature over the conterminous 48 states in 2012 was 0.555 C (about 0.99 degrees F) warmer than seasonal norms.

With regard to global average temperatures, 2012 was only the ninth warmest year amongst the last 34 years....

...with an annual global average temperature that was 0.161 C (about 0.29 degrees Fahrenheit) warmer than the 30-year baseline average, according to Dr. John Christy, a professor of atmospheric science and director of the Earth System Science Center at The University of Alabama in Huntsville. 2012 was about three one-hundredths of a degree C warmer than 2011, but was 0.23 C cooler than 2010.

Eleven of the 12 warmest years in the satellite temperature record have been been since 2001. From 2001 to the present only 2008 was cooler than the long-term norm for the globe. Despite that string of warmer-than-normal years, there has been no measurable warming trend since about 1998. The long-term warming trend reported in the satellite data is calculated using data beginning on Nov. 16, 1978.

Although the warmest years have occurred in recent years, Christy pointed out last month that global average temperatures have been essentially flat since 1998: 

Since 2002, there has been a plateau of relatively warmer temperatures with only 12 months when the global average temperature was cooler than the long-term seasonal norm. In fact, compared to the 30-year temperature baseline, the most recent five years (12/07-11/12) averaged only 0.003 C (0.173 to 0.176 above seasonal norms) warmer than the preceding five years (12/02-11/07). ...

The long term 0.14 C per decade warming trend measured by microwave sounding units on a series of satellites is consistent with the low-end of global climate change predictions made by some climate models; it is also within the potential range of natural climate variability, especially since most of the warming happened over such a short period of time.

Below are the newest data updated through December, 2012:

Go here to see the monthly satellite data.

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  • A Serious Man||

    So what temperature should the Earth be, exactly?

  • tarran||

    It should be maintained at the exact same rate that it was before the patriarchy started raping Gaia with its dildo made from petroleum products.

  • ||

    The same as your mom?

  • John Galt||

    Whatever temperature best fits Lefty's pseudo-scientific argument.

  • Bardas Phocas||

    It's an issue of 'Fairness' not any exact level of degrees.

    So let's increase taxes some more with a penaltax tied to the aggreagate tempeture.

  • John Galt||

    Exactly, there are peoples in the world much less productive and financially well off, by penaltaxing us into equal poverty the agg. temp. with be lowered made more palatable.

  • John Galt||

    will be*

  • T o n y||

    There is no ideal temperature for the whole earth. It could be said that there are ranges of optimal temperatures for the various climate zones/ecological niches. These do change, and when they change gradually, life adapts. When they change rapidly, as they are now, there tend to be mass extinction events. When people talk about preserving a certain climate status quo, generally they mean what is optimal for human beings. That we're already in the midst of a major global extinction event doesn't seem to concern too many everyday people.

  • Juice||

    The Younger Dryas ended over a period of about 50 years more or less. That's a temperature swing of about 6-8 C in mere decades. What was the extinction rate then? Was it a major global extinction event? What was the rate then as compared to today?

  • T o n y||

    Lots of stuff is in dispute about the Younger Dryas period, and you're asking about the effects of its abrupt end--but the period itself is considered geologically brief (still about 1,300 years) and probably resulted in the extinction of most of the megafauna in North America and possibly the decline of the Clovis culture of humans. Human-caused global warming of the current era is a much more rapid change and is already having massive effects on global species. Isn't it all the more fruitful to look at what's going on right now?

  • Juice||

    Much more rapid than an increase of 6-8 C within 50 years?

  • ||

    How exactly is a .5 difference between 1979 and now rapid change? How is a plateau rapid change?

  • Canman||

    Willis Eschenbach on extinctions:

    http://www.youtube.com/watch?v=2KOyFvA5f1A

  • ||

    I can't wait for TEAM HOT to tell us what this means. Oh wait, I already know what they'll say: CONTROL.

  • ||

  • John Henry||

    Now another paper, by Esper et al published in the Journal of Global and Planetary Change, shows that not only was the summers of the MWP equal or greater than our current warmth, but that the summers of the Roman Warm Period of 2000 years ago were significantly warmer than today.

    From here. So to all the alarmists out there, STFU.

  • ||

    Well OF COURSE it was warmer 2000 years ago. Look at all those Romans running across Europe wearing nothing but those little skirts.

  • ||

    Yeah, I put as much faith in someone being able to tell me how warm it was 2000 years ago as I do in someone telling me how warm it was 200 years ago. Refuting shit science with shit science is...shit.

  • John Henry||

    Epi,

    We know that is was warmer then than now because of the types of foodstuffs that they grew in those regions. They grew olives and wine grapes in regions that today is too cold to support them. I agree that no one can tell you what the temperature was 200 or 2000 years ago, but they can tell you whether it was warmer or colder relative to today.

  • ||

    They used green houses, warmed with C02 obtained from ice-core samples in Antarctica. That's why the Ice-core samples had less C02 back then.

    It's C02 all the way down.

  • SugarFree||

    Goddamn the mild November and December we had in Kentucky, goddammit I say!

    I shudder to think that it was almost warm enough to eat Thanksgiving dinner outside. What a fucking horrific fate we barely dodged!

  • Tman||

    Same in Nashville, but I fear that may have been short lived. We are in witches teat area over the last week or so.

    And we have also had that awesome 32 degrees and pouring rain weather lately, or as I explain to my non-Yankee friends "Beautiful New England Fall Weather".

  • John Galt||

    It's been so abnormally cool in my part of the country that for the second year in a row the returns from our gardens have been unusually meager.

  • John Henry||

    It's been so abnormally cool in my part of the country that for the second year in a row the returns from our gardens have been unusually meager.

    Wait, are you saying that global temperature isn't uniform? And that some places will have warmer weather and some will have cooler weather? I thought Gaia was getting hotter all over.

  • John Galt||

    By my observations, that would be correct.

  • sarcasmic||

    Warming causes cooling. That's what they say, seriously. Warming disrupts weather patterns that bring warm air to cold places, causing them to cool.

    Heads they win! Tails you lose!

  • ||

    Behold, Saccharin Man, my wintry weather for last Dec. Though I like cold weather, I envy thee some.

  • Brett L||

    I know. I was walking on the beach last weekend in jeans and a t-shirt. The Canadian snowbirds thought the Gulf was too warm to swim in.

  • Kroneborge||

    Most trends don't go straight up, they bounce around, if you look at the trend the overall trend is up, draw some trend lines, or do a moving average, the trend is clear.

  • Jesus H. Christ||

    Depends on where you start and stop the line. Honestly, during the Great Bombardment the surface of Earth was liquid molten rock. How hot do you think it was then?

  • T o n y||

    And these are Bailey's cherry-picked University of Bumfucksville scientists who don't by any means represent the mainstream of the field.

    Ayn Rand's corpse could write a post declaring global warming real and most people here would choose to stop liking Ayn Rand than believe it.

  • Juice||

    Can I detest Ayn Rand and not be alarmed about global warming at the same time?

  • T o n y||

    You can do whatever the hell you want.

  • Juice||

    Can I quote you on that in the future?

  • Ron Bailey||

    T: Cherrypicked data? You're just venting, right? It's data from NOAA satellites. I really don't know what to say to such an absurd and groundless assertion.

  • T o n y||

    Cherrypicked scientists. Ron you should realize by now that I'm more on your side than most people here.

  • Juice||

    You see it's data from NOAA satellites, but it was reported by the WRONG scientists from the WRONG university.

  • ||

    The problem Ron is that you mentioned a university in the South and, as we all know, people from the South are just retarded imbred hicks. Next time Tony needs you to mention San Diego or someplace in New York.

  • T o n y||

    Whereas experts from Oxford can be universally dismissed, because of something you read on a rightwing website.

  • Knutsack||

    So, can we expect the new acronym to be AUSAW? Anthropogenic United States of America Warming?

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