.."The scientists used the seven-to-nine years of observations from these satellites to map "normal" rainfall and greenness conditions in non-drought years. When they compared those conditions to the same months of the 2005 drought, the researchers found that areas of Amazon's intact forests that had received below-normal rainfall in 2005 also had above-average greenness."..more there

ed: sure doesn't work like that here! You get a drought, all the trees show it, none of this "lag" time stuff. Our front yard oaks and pecans have maybe 30-50% less foliage coverage (seems to be less and a lot smaller leaves) with a normal year (half the shade in other words). This summer it is has been *hot*, and now that it is fall we are still getting 90 + F days, although it has been cooler at night now thankfully.