2010: The Hottest Year of Debate
June 2, 2010 by jason
Between the release of Apple's iPad and BP's big blunder, the scientific/technology news sector seems to have been too busy to focus on climate change. Something which only recently struck my attention is an April 15th article by the National Oceanic and Atmospheric Association (NOAA), which stated that:
Quote:
The combined global land and ocean average surface temperature for March 2010 was the warmest on record at 56.3°F (13.5°C), which is 1.39°F (0.77°C) above the 20th century average of 54.9°F (12.7°C).
Source: Depths and drilling times of the two EPICA Dome C drilling sites (source: NOAA: Global Temps Push Last Month to Hottest March on Record)
To graphically illustrate what was being said here, I downloaded a dataset of global land-sea temperatures from the Goddard Institute for Space Studies (GISS) Surface Temperature Analyses. By taking only values from March measurements, I was able to reproduce this plot of average land-sea temperature in March over the past century:
Graph of Global Average Land-Sea Temperature in March for the past 130 years
According to the GISS data, the March of 2010 clocks in at second place with 14.83°C, slightly cooler than the 14.85°C average in March of 2002. Whatever the cause might be for the difference in values between the GISS and NOAA results, the consensus is clear: the past 10 years have seen unprecedented temperatures, unseen since we began taking accurate measurements over a century ago.
Is this really part of a trend?
I found the article mentioned at the beginning of this article interesting because I was starting to become skeptical of the idea that global warming was a continuous trend since the 1970s (as I had alluded to in previous global warming articles), due to an apparent softening in the temperature increases which seemed to begin somewhere at the end of the 20th century. Combining the GISS temperatures dataset with data from the National Oceanic & Atmospheric Administration I was able to put together this graphical representation of the doubts I previously described, dubbed by many to be a phenomenon of global cooling:
Graph of Global Average Land-Sea temperature against CO2 Concentrations for the Period 2002-2008, outlining one of arguments for the occurrence of global cooling in the 21st century.
I can see now why the idea of global cooling took such ground over the past decade or so. Up until the end of 2008, it almost appears as if the 21st century has cooled instead of heated up, while CO2 itself has continued on its merry path upwards. However, if you look at the big picture, taking the past 25 years and including the most recent data, we can see that this simply isn't what has been happening:
Graph of Global Average Land-Sea temperature against CO2 Concentrations for the period 198-2010
I think it's quite difficult to deny the existence of a correlation here, despite the slight deviations that occurred several years ago. To drive home the point that it is still getting hotter, let's take a look at the past 60 years:
Graph of Global Average Land-Sea temperature against CO2 Concentrations for the Past 60 years
CO2 Concentration data was obtained courtesy of the National Oceanic & Atmospheric Administration, temperature data courtesy of GISS Surface Temperature Analysis)
- jason's blog
- Login or register to post comments
Comments
Re: 2010: The Hottest Year of Debate
December 14, 2010 by Anonymous (not verified)
60 years! What about 200 years or a thousand!
Re: 2010: The Hottest Year of Debate
December 14, 2010 by jason
Well, over longer timescales the correlation becomes even stronger. Take this plot of temperature vs. CO2 concentrations over the past 50,000 years (from http://www.warmdebate.com/correlation-between-temperature-and-co2-statis...):
The correlation is extremely close. In fact, it's about 90% (from the same article). However, much of that correlation took place in a time where anthropological CO2 emissions were negligible to non-existent. The point I was trying to make with this article is that we can still see a correlation today, where, for the first time in earth history, human emissions of CO2 are contributing so significantly to global CO2 concentrations that they are without a doubt increasing independently of temperature. A corresponding correlation between CO2 and temperature could therefore indicate CO2 as a driver of temperature, rather than a feedback element.
Re: 2010: The Hottest Year of Debate
December 15, 2010 by Anonymous (not verified)
As you suggest 'CO2 concentrations are increasing independently of temperature'. Although CO2 might be a driver of temperature, historical records indicate that temperature could be the driver of CO2 levels. The last twenty years are too short to draw any conclusions on this either way. One could infer from your first graph that temperatures are levelling off despite increasing CO2 but again it is too early to say.
Re: 2010: The Hottest Year of Debate
December 20, 2010 by madmike.davies@...
CO2 is the measure of Ave temp, the value of absolute temp is a function of insolation, because insolation is currently at a minimum then the effect of CO2 on temperature is unseen, over the next 14,000 yrs global temp will rise from the current low level to a level about a mean defined by CO2 levels, but should be less than 2 degC
Re: 2010: The Hottest Year of Debate
December 21, 2010 by Anonymous (not verified)
Thank you that makes a lot of sense. It is of course hard to predict the next 14,000 years but a 2 deg temperature rise seems eminently reasonable.
Re: 2010: The Hottest Year of Debate
January 1, 2011 by Gary (not verified)
No doubt the temperature is going up, but I haven't seen good proof that co2 drives temperature as opposed to temp driving co2. The last chart shows a regular rise and fall of temperature over thousands of years and it appears this latest rise could well correspond to that pattern.
I'd like to see less debate about warming and more rigorous research into what is causing the warming. Also, if the 450,000 year pattern holds, we should realize we may be heading for dramatic cooling in a few centuries or millennia from now. It could be that we've been living through a blessed period of warmth, fueling the ability for humans to develop advanced societies. If the pattern holds true, that warming cycle will peak in the coming centuries (heralding extreme weather), and then drop precipitously.
In short, maybe the best we can do is prepare for climate change; but not take the credit or the blame for it.
Just sayin'...
Re: 2010: The Hottest Year of Debate
January 2, 2011 by jason
It's a complex issue. An interesting discussion on this here: http://www.warmdebate.com/forum/facts-about-global-warming-discussion
Check the discussions between myself and Sentient, he had some very interesting things to say. Temperature has increased over the past 40 years or so, but much evidence is pointing to a decline in temperature in the current 30 year period. The strongest argument for this is a recent and somewhat groundshaking article published only a few months ago: http://www.fel.duke.edu/~scafetta/pdf/scafetta-JSTP2.pdf
As for what is causing the warming; I think the strongest evidence (including the evidence summarized in scafetta 2010 above) points towards steady oscillations in temperature by extraterrestrial factors such as orbital variations, which a general trend towards warming caused by anthropological global warming. If you want my opinion; over the next 30 years we will see a slight cooling trend from the orbital patterns as described in scafetta, but these will be strongly challenged by anthropological CO2 forcing, causing a slower decrease in temperature than the increase we saw since the 70s (where orbital factors coupled with CO2 increases to cause drastic warming). The 30 year period following the current (from 2030 up to the 2060s-70s) will see even more powerful warming than previously experienced, and will most likely herald the catastrophic warming that Al Gore has been raving about all this time. Of course by the 2050s we will have relegated Mr. Gore to the history books and long concluded that AGW was nothing but a bunch of hype, much like the Millenium Bug that we all heard so much about...
Re: 2010: The Hottest Year of Debate
January 4, 2011 by Gary (not verified)
Okay, now I'm confused. So, the conclusion is, it's either getting hotter, or colder. I think I'll cover both bases by going out and buying a parka and some mukluks, plus a speedo and a 45 gallon drum of sunscreen. Personally, I think Gaia is going to snap back at about three or four degrees over the 1970 average, and then plunge us into winter for a few millennia. At that point, we'll need all the CO2 we can get!
In the Year 4510, I plan to open a Hummer franchise.
BTW, thanks for the great posts ... snide comments aside, this is the best site I've seen on the debate.
Re: 2010: The Hottest Year of Debate
January 5, 2011 by madmike.davies@...
Gary,
Buy some bermudas, its going to get hotter, but figure on being 1000 yrs old before it happens. If you really believe in GAIA then assume that CO2 is actually the agent of gaia, it will keep us warm while insolation is low and will then be absorbed by the biosphere as we start to heat up see my blogs
http://www.warmdebate.com/users/madmikedavieshotmailcom
http://madmikedavies.wordpress.com/
CO2 will keep us warm as long as levels stays above 300 PPM while insolation is at a minimum which it is now, and will keep it livable if it stays below 1000 ppm while insolation is at a maximum which it will be in 14,000 yrs. see vwikipedia article on Milankovich cycles
Re: 2010: The Hottest Year of Debate
January 8, 2011 by jive
It really depends a whole lot on how you look at the issue; Yes, it's unlikely that CO2 increases will kill us and destroy life on this planet as we know it. But what about the effects that small changes will have on our ecosystems? We've already been the cause of thousands of extinctions on this planet, how much worse will it be if we begin affecting temperature? Fine, nature will survive, but at what cost?