What was done
Interannual variations of Tibetan Plateau vegetative productivity were investigated using a 21-year (1982-2002) normalized difference vegetation index (NDVI) dataset to quantify the consequences of changes in temperature and precipitation for the regional ecosystem.

What was learned
The authors report that "the maximum, minimum and mean temperature fluctuations all present an increasing trend over the 21 years," and that "the NDVI is comparatively large during the warm years, such as 1988, 1994, 1998 and 1999," and that "relatively small NDVI values are well coupled with the cold extreme and mean temperature in 1982, 1983 and 1997." This type of relationship, as they continue, "suggests a positive correlation between vegetation activity and surface air temperature on the plateau," and in this regard they report that "the correlation coefficient between the NDVI and the maximum, minimum and mean temperature reaches 0.674 (significant at the 99% level), 0.53 (significant at the 95% level) and 0.55 (significant at the 99% level), respectively." In contrast, they find that "the precipitation fluctuation does not show a detectable trend, and therefore its correlation with DNVI is not obvious."

What it means
Zhou et al. conclude that "vegetation variability on the Tibetan Plateau might be mostly driven by thermal impacts (i.e., surface air temperature), whereas precipitation impact is less clear." Overall, they say "vegetation activity demonstrates a gradual enhancement in an oscillatory manner during 1982-2002," suggesting a significant positive impact of what climate alarmists call "unprecedented" global warming over what Zhou et al. describe as "one of the most prominent features on Earth."

This good-news story is the type of thing that is generally not "shouted from the housetops" in our "new age of enlightenment," but it is typical of what is happening worldwide on a long-term basis, as the inexorable greening of the earth continues.