Joshua Trees at Pierce Ferry, AZ

This image, from April 2004, shows mortality of some adult Joshua trees resulting from years of hot-dry climate. During the prior year, this area received only 17 percent of its average precipitation and was 4 degrees F warmer than average -- conditions that are projected to become even more frequent in models of future climate. Seedlings and saplings in this southerly stand of Joshua trees are rare to non-existent.