The White House document - a climate status report required periodically by Congress - contains no new research. But it paints a fuller and darker picture of global warming in the United States than previous studies and brief updates during the George W. Bush years. Bush was ultimately forced by a lawsuit to issue a draft report last year, and that document was the basis for this new one.
In the Northeast, people are already experiencing more frequent days above 90 degrees Fahrenheit, longer growing seasons, increased heavy precipitation, reduced snowpack, and earlier ice breakup on lakes and rivers, the report says. As emissions rise, those changes will amplify with shorter winters and more erratic weather. The region’s $7.6 billion snow and ice sport industry will continue to suffer, with ski operators forced to make more snow. The region’s snowmobile season could be non-existent by mid century.
Off New England, the report predicts cod populations - already stressed from overfishing - will find warming waters inhospitable. Cod are adapted to a wide range of ocean temperatures yet studies show increases above an annual bottom temperature of around 47 degrees Fahrenheit will lead to a decline in growth and survival - and large populations of the fabled fish are not found above 54 degrees Fahrenheit. The report projects that those thresholds could be met or exceeded this century. The center of the lobster fishery - already moving northward - will continue to migrate with warming temperatures.
The report also projects that, by late this century, heat stress on dairy cows in Massachusetts and southern Vermont, New Hampshire and Maine, could result in up to a 20 percent decline in milk production. Northern New England dairy production, however, is not expected to be affected.
One administration official, Jane Lubchenco, called the new report a game changer that would inform policy but not dictate a particular solution.
Beth Daley of the Globe staff contributed to this report.
