Some climate cooling caused by past volcanic eruptions may not be evident in tree-ring reconstructions of temperature change, because large enough temperature drops lead to greatly shortened or even absent growing seasons, according to climate researchers who compared tree-ring temperature reconstructions with model simulations of past temperature changes.

Engineering our way out of global climate warming may not be as easy as simply reducing the incoming solar energy, according to a team of University of Bristol and Penn State climate scientists. Designing the approach to control both sea level rise and rates of surface air temperature changes requires a balancing act to accommodate the diverging needs of different locations. "Basic physics and past observations suggest that reducing the net influx of solar energy will cool the Earth," said Peter J. Irvine, graduate student, University of Bristol, UK, and participant in the Worldwide Universities Network Research Mobility Programme to Penn State. "However, surface air temperatures would respond much more quickly and sea levels will respond much more slowly."

Both climate change and humans were responsible for the extinction of some large, cold-adapted, plant-eating mammals, according to research that is the first of its kind to use genetic, archeological, and climatic data together to infer the population history of large-bodied Ice-Age mammals. The research will be published in the journal Nature.

The study's findings are expected to shed light on the possible fates of living species of mammals as our planet continues its current warming cycle. Beth Shapiro, the Shaffer Associate Professor of Biology at Penn State University, is a member of the research team. High-resolution images are online at
http://www.science.psu.edu/news-and-events/2011-news/Shapiro10-2011

Conservation and international aid groups may be on the wrong course to address the havoc wreaked on tropical rainforests by climate change, according to a commentary co-authored by Penn State Professor of Biology Eric Post appearing in the journal Nature on Dec. 2. "Most of the world's terrestrial biodiversity is contained in tropical rainforests, and climate change is looming ever larger as one of the major threats to these ecosystems, but how humans deal with climate change may be even more important," said Penn State Professor of Biology Eric Post, one of the letter's authors.

Susanne Moser, research associate at the University of California-Santa Cruz Institute for Marine Sciences and director of Susanne Moser Research and Consulting will discuss ways that scientists can enhance communication with the public on climate change as part of this year's EarthTalks series at 4 p.m. on Monday, Sept. 13, in room 112 of the Walker Building on Penn State's University Park campus.

A panel of leading scholars has cleared well-known Penn State climate scientist Michael Mann of research misconduct, following a four-month internal investigation by the University.