However, given the remaining uncertainties, which the authors discuss in their paper, a firm upper boundary is still elusive. (dotearth.blogs.nytimes.com)
NYT's Revkin chides Hansen for promoting sea level claims that are at upper boundary of what is «even physically possible» (climatedepot.com)
There's a mantra in the trade that lower boundary treeline trees are precipitation proxies and upper boundary tree lines are temperature proxies, relying on Lamarche 1974. (climateaudit.org)