I think I might just briefly mention the recent Sherwood & Nishant paper, Atmospheric changes through 2012 as shown by iteratively homogenized radiosonde temperature and wind data, which appears to show what some have called a tropospheric hot spot. It’s also been covered elsewhere. As the abstract of the paper says (my bolds)
Temperature trends in the updated data show three noteworthy features. First, tropical warming is equally strong over both the 1959–2012 and 1979–2012 periods, increasing smoothly and almost moist-adiabatically from the surface (where it is roughly 0.14 K/decade) to 300 hPa (where it is about 0.25 K/decade over both periods), a pattern very close to that in climate model predictions. This contradicts suggestions that atmospheric warming has slowed in recent decades or that it has not kept up with that at the surface. Second, as shown in previous studies, tropospheric warming does not reach quite as high in the tropics and subtropics as predicted in typical models. Third, cooling has slackened in the stratosphere such that linear trends since 1979 are about half as strong as reported earlier for shorter periods.
As I understand this, it is indicating the the rate of warming in the troposphere exceeds that at the surface. This is essentially because water vapour does not condense (and release latent heat) equally at all altitudes. It tends to do so more in the at altitudes where the pressure is around 200mb (a few km above the surface) than it does at the surface. This leads to faster warming at these altitudes in the troposphere than at the surface, and produces a negative lapse rate feedback.
In general, it seems that this result is broadly consistent with climate models, but that there are some differences, such as it not reaching quite as high in the tropics and sub-tropics as predicted. I don’t quite understand the significance of this. I also don’t quite understand the significance of stratospheric trends being about half as strong as reported earlier. Maybe others who do could clarify in the comments. Overall, however, this seems to be an important results which appears to confirm our basic understanding. I’m looking forward to Turbulent Eddie accepting that we now have evidence for a tropospheric hot spot 😀