In Changing Ecosystems, Winners and Losers

Ponderosa pines, above, lodgepole pines and noble firs could become less common in northwestern forests thanks to climate change.

Two new peer-reviewed studies, one about forests and the other about oceans, predict that existing ecosystems will rearrange themselves over the next 70-plus years in response to global warming.

In one of the studies, to be published in the journal Remote Sensing of Environment, scientists from Oregon, Montana and British Columbia writethat northwestern forests removed from the climatic buffering effect of the Pacific Ocean will transform themselves to adapt to less rainfall as well as warmer temperatures at high altitudes.

Species that dominate sub-Alpine landscapes at high elevations, like the Ponderosa pine and lodgepole pine, will recede, the study predicts.

“At the same time, more temperate species such as Douglas fir, grand fir and western hemlock are favored to invade and eventually replace the current dominants,” the authors write.(The impact of beetles on forests of lodgepole pine was noted here a few months ago.)

Another study, by scientists associated with the Scottish Marine Institute and the Farallon Institute for Advanced Ecosystem Research, suggests that temperatures and ecosystems are changing even faster offshore.

“Geographic shifts in temperature bands, known as isotherms, in the sea have outpaced those observed on land,” William J. Sydeman, one of the report’s authors, said in a press release. He added, “We should not be surprised when we see substantial change in the whereabouts of marine populations or changes in their timing of breeding or migration dates,”

The study, whose lead author was Michael T. Burrows of the Scottish Marine Institute’s Department of Ecology, appears in the latest issue of the journal Science.

Monterey Bay Aquarium Research InstitutionHumboldt squid are moving north.

Along the California coast, salmon populations have been trending downward while the tropical Humboldt squid, which can grow to 100 pounds, has beenseen more frequently.

But the authors caution that the changes will be more pronounced in some ocean regions, like the Gulf of Alaska, than others. The waters off the Northern California and southern Oregon coasts have not followed the warming trend; in fact, they have been cooling slightly.

In the forests study, the issues identified by the researchers Richard H. Waring, Nicholas C. Coops and Steven W. Running track those raised by my colleague Justin Gillis in his examination of the role of forests and the threats they face in a warming environment.

The researchers set out to pinpoint exactly how forests have been changing in recent years and how things are likely to play out for various species in the future. The greatest changes, they predict in this paper and another recent one, will continue to occur at the northern and southern extremes of forests in the Pacific Northwest. In the north, invasive beetles are likely to be the strongest driver of change; in the south, it is likely to be fire.

Most climate models predict “that the Pacific Northwest region as a whole will become progressively warmer, by 2 to 5 degrees (Celsius) by 2080, with perhaps somewhat more precipitation in the winter and spring, and less during the summer,” they noted.

They added, “These trends accentuate those observed over the past century.”