Recent studies are shining light on public health, forced migration, and sea level risks facing northeastern U.S. and Canadian shorelines.

Some observers are saying the would-be news-consuming public may have over-dosed on climate news for the time being. If so, what about health news?

‘Biggest Global Health Threat’

“The biggest global health threat of the 21st century,” is how a recent research paper in the respected British medical journal Lancet characterizes climate change.

The report, for reasons no one may ever know, attracted relatively scant coverage throughout much of the U.S., but the authors cautioned that “Effects of climate change on health will affect most populations in the next decades and put the lives and wellbeing of billions of people at increased risk.”

‘Vast Human Migration’ Risk

A recent report from a United Nations-funded collaboration resulted in publication in Forced Migration Review of a series of articles examining the extent of potential population displacements, community adaptation and coping strategies, and efforts to address migrations brought about by global change. The review, available at www.fmreview.org/climatechange.htm, is published by the University of Oxford’s Department of International Development and is available in hard copy in English, Arabic, French, and Spanish.

In a statement on the report, Columbia University’s Center for International Earth Science Information Network, CIESIN, whose researchers authored the study, headlined that climate change “could drive vast human migrations … displacements are already underway.” The CIESIN researchers cautioned early that “the effects of climate are hard to sort from connected factors including political and economc conflicts, extreme weather events, population growth, human destruction of ecosystems, and overuse of farmland.”

But they said in a release that “climate change will eventually play a dominant role by exacerbating all of these problems, and is already having detectable effects.”  Again pulling back some, they gave no estimate of those “potentially uprooted,” but pointed to other researchers’ estimates of 25 million to 50 million by 2010 and nearly 700 million by 2050.”

“Climate is the envelope in which all of us lead our daily lives,” said CIESIN geographer Alexander de Sherbinin, cautioning of “warning bells” in the study.

Greenland Ice Melt Risk to Northeastern U.S., Canada

It’s a National Center for Atmospheric Research (NCAR) study, published May 29 in Geophysical Research Letters, that is putting Boston, Halifax, New York, and other cities in the northeastern U.S. and Canada in news stories dealing with projected sea level rise.

“Major northeastern cities are directly in the path of the greatest rise” from accelerating Greenland ice sheet melt and resulting sea level rise, according to lead author Aixue Hu, of NCAR. Building on a March study published in Nature Geoscience, the authors of the new study said that at moderate to high melt rates, heavily populated areas of northeastern North America could see an additional 4 to 12 inches of water “on top of average global sea level rise.”

They say the northeast coasts of North America are “especially vulnerable to the effects of Greenland ice melt because of the way the meridional overturning circulation acts like a conveyor belt transporting water through the Atlantic Ocean.” A 3 to 7 percent annual increase in the rate of Greenland ice sheet melting would lead to a warming of deep water and result in expansion and elevation of surface water across parts of the North Atlantic, they said.

Co-author and NCAR scientist Gerald Meehl said in a statement that “ocean dynamics will push water in certain directions, so some locations will experience sea level rise that is larger than the global average.”