Is there any possible natural reason for the entire globe to be .79 degrees warmer than last year?

http://discover.itsc.uah.edu/amsutemps/execute.csh?amsutemps

This is from the UAH satellite data which Christy and Spencer assert is much more accurate than ground-based measurements and avoid Urban Heat Island distortions. The average global temperature at the surface level yesterday was .79 degrees warmer than the same date just a year ago. At this time last year we were in a El Nino pattern, now we are in a La Nina which is cooling the ocean surface, but the apparently warming of land is overwhelming that. The sun is still in a quiet period. .79 degrees in one year is a huge one-year increase (more than double the increase that the IPCC projected for each decade). I do understand that there is variation every year, but is there any possible natural reason for such extreme warming in one year especially considering that the strongest known natural variants would be contributing to cooling?

Even if some quirk in the data could explain the extreme increase on a specific date, is there a natural factor that could explain any warming versus last year?

2010-08-19T11:09:10Z

Let's remember here: the sun has not done anything to increase temperatures, and the long run cycles are in a very slow cooling patterns. Those are not possible answers.

2010-08-19T11:10:23Z

And this is the average of the entire world -- it is not weather in a particular place. This is the entire system.

2010-08-19T12:45:30Z

Edward, are you aware the projections are only .2 degrees per decade? .79 degrees in a year is huge. 2-3 degrees in a decade would be catastophic. 2-3 degrees in one year is beyond imagination.

2010-08-19T12:47:54Z

2-3 degrees in a century is the extremely rapid rate that is causing potentially catastrophic changes.

2010-08-19T14:25:09Z

Corrected link. They've added a day and the difference is down to .75 degrees.

http://discover.itsc.uah.edu/amsutemps/execute.csh?amsutemps

2010-08-19T14:29:45Z

Arrg. The site is broke.

Use this link and toggle to "near surface layer"
http://discover.itsc.uah.edu/amsutemps/execute.csh?amsutemps+002

Dana19812010-08-19T11:02:25Z

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Yes. Frankly there must be, because the AGW signal is pretty consistent at ~0.02°C per year. There wasn't a sudden jump in atmospheric CO2.

It's true we're entering a La Nina phase, but at the same time, there's about a 6 month lag before changes in ENSO are reflected in the satellite temperature record. 6 months ago we were still in the midst of the El Nino cycle. There are of course other cycles too - NAO, AO, PDO, and so on which could also be contributing to the difference.

*edit* how funny is it that David said the same thing as me and has 1 thumbs-down while I have 16? Just goes to show that deniers give thumbs based on the answerer and not the answer.

Paul, if you really think the planet is going to warm 8°C over the next decade, I've got a bridge to sell you.

Joan2016-04-13T06:56:27Z

I'm no time series analysis expert, but my opinion is that you can't use standard t-tests for comparing means of time series data because the assumption of independence is immediately violated in time series data and, no, I don't think anomaly data would follow a normal distribution (but what do I know?). I would think that significant warming would mean that deltaT is significant in relation to time, but your method of comparing means from two different time periods seems like it should at least provide some inkling of information. Linear regression can be use to test for significance but this violates the independence assumption the same as other parametric methods. I can run simple regression tests with a graphing software package I have if you'd like to send me the data somehow.

virtualguy921072010-08-20T10:10:51Z

Your question points out the problem with using global surface temperature as a measure of global warming.
Global climate is a function of the heat content and distribution of heat within earth's envelope - oceans, land surface and atmosphere. In this system, the atmosphere contains the least heat, has the greatest temperature variability, has the most complicated relationship between heat and temperature due to phase changes in water vapor, and has the most rapid response times. Atmospheric temperature, in short, is the noisiest signal that you can monitor to determine global climate.

Total ice volume, oceanic heat content, and net radiative flux at the top of the atmosphere are much more precise measures of what our climate is doing. As instrumentation in these areas improves, we are getting a much better picture of what climate is doing. Air temperatures, meanwhile, will continue to be a noisy byproduct of what is going on.

Anonymous2010-08-23T05:26:33Z

"The reason why the increase has been so much greater this year than previously is because the heating has undergone a very rapid and likely catastropic [sic] acceleration."

Ok Mr. We Will Have No Unsupported Assertions, on what do you base this?

I happen to agree with you, but that's just my intuition.

What about delayed feedback from thermal saturation of the oceans? What is the current rate of increase of methane concentration, has it changed? Could we recognize a chaotic shift if one was occurring?

Rio2010-08-19T12:18:48Z

Sure there is, it's called (masking) any temperature extreme consolidated into an average hides both the lows and highs. The big question is what geographical locations due to what effects are responsible for the masking?

ed: If that's what your asking, nor does your link work.
I do understand the difference between a decade and one day, wish others did.

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