Setting the record straight | Satellite puzzle solved

If greenhouse gases are warming the Earth's surface, climate models say the same thing should be going on in the troposphere — the lower layer of atmosphere where weather occurs.

The fact that weather balloons and satellite measurements from the past 25 years didn't show the predicted warming provided climate-change skeptics with one of their strongest arguments, until recently.

The satellite data have long been controversial and messy. Orbiting high above the poles, the instruments measure temperature indirectly, by analyzing microwave radiation. They peer down through the entire atmosphere, which makes it hard to differentiate between layers. Scientists also must rely on statistical tricks to stitch together data from different satellites launched over the years.

Last month, three studies pointed out errors in those calculations, including failure to factor in the way the satellites drift in orbit, which can lead to confusion between nighttime and daytime temperatures. When corrected, both the satellite and balloon data showed heating.

Those results add to findings published last year by University of Washington climate scientist Qiang Fu. He asked if warming might be masked by rapid cooling in the upper atmosphere, which was predicted as a byproduct of greenhouse warming.

He developed a new way to subtract out the cooling, and found the troposphere was heating up in near-perfect synchrony with the surface below.

Taken together, the new studies show the lower atmosphere is heating up at rates predicted by global climate models.