We’ve often looked at some of the tricks deniers use to make global warming seem nonexistent. But perhaps the most common of all is to focus on the noise rather than the signal in data. And perhaps their favorite way to do so is to choose a time span so short that the signal is almost invisible while the noise dominates. That’s their strategy — make noise.





While climate is typically defined as 30 years, those in denial will happily use less than a year. Hell, they’ll even use a single month, or a single snowstorm, or whatever they can get their hands on to make the globe seem cold — even for a moment. It’s their modus operandi. In fact I have a prediction: that Bob Tisdale will deny he meant what he meant with his deceptive graph tricks, instead he’ll plead that he was just talking about the “trend” since 2003. Yeah … since 2003.

It’s all smoke and mirrors.

And it depends on the fact that just about every geophysical variable shows short-term noise. In fact “short-term” doesn’t just mean day-to-day fluctuations, but month-to-month and year-to-year fluctuations. They’re very real. And they’re noise, not signal.

One cure for the short-term noise is to smooth the data. And one of the most reliable, and simplest, ways to smooth is nothing more complicated than just to average the data over longer time spans. So, let’s take some climate-related data and average it over time spans longer than a single year. I won’t even get all “climatic” on you and insist on 30-year averages, I’ll keep it short — let’s use 5-year time spans. Frankly, 5 years isn’t a long time in climate terms, it’s not at all impossible for even 5-year averages to “buck the trend” for no other reason than random noise. And for some of these data the latest 5-year period is incomplete, which will make the noise even bigger and increase the chance of accidentally contradicting the trend. But hey, let’s compute them and see what happens.

We’ll start with global temperature from NASA:

No doubt about that one. When the noise is cleared away, the trend is crystal-clear. Upward.

How about sea level?

Watts & co. love to go to extreme short time scales with this one — ludicrous short times. But the long-term trend is still clear. Upward.

How about ocean heat content?

Let Bob Tisdale and Anthony Watts focus on too-too-short time scales — when you look at the big picture, again the trend is clear. Upward.

What about the “canary in a coal mine,” the Arctic? It’s temperature trend is way faster than the global average:

Not only is the trend clear, it’s downright scary. Upward.

And how about the extent of sea ice in the Arctic?

Another clear, inexorable trend, and as expected in a warming world, it’s downward.

How gullible do you have to be not to see what’s really happening? How long will people swallow the “trend reversal last year” bait hook, line, and sinker — only to be fed a different bait as each one resumes its trend and the deniers have to switch to another? As for Watts, Tisdale, Goddard, Morano, etc…. how do you explain the fact that when we stop focusing on momentary ups-and-downs, so many trends become so clear, so obvious, so steady, for so long?

What’s the cause of the global warming, the trend which hasn’t shown any sign of stopping or even slowing down?