Must reading for sportsmen and other conservationists: The draft report of the latest National Climate Assessment.

The Global Change Research Act of 1990 requires an assessment report at least every four years. It is put together by the 60-member federal National Climate Assessment and Development Advisory Committee, whose work was reviewed by the National Academies of Science.

The news isn’t good: the climate is rapidly warming, sea rise is accelerating, oceans are acidifying, and wildlife populations are being displaced as habitat changes – and all of this is conclusively proven to be human caused, primarily though the use of fossil fuels.

Of course, none of this is news to sportsmen. While some have tried to discredit the science with politics, hunters and anglers were among the first segments of our society to ring alarm bells, citing field observations to back up their concerns and their belief in the science spelling out this environmental disaster.

This latest report continues the steady intensification of warnings and rock-solid conclusions about causes and impacts that have been a trend throughout its existence. (Earlier reports can be found at the U.S. Global Change Research Program site.)

This draft, plus appendices, is more than 1000 pages long, all of it important to the future shape of public hunting and fishing in the U.S. – not to mention human health and living standards. But reading the Executive Summary and the 11 key Report Findings will give sportsmen a good overview of where we stand – and where we’re headed, unless action is taken soon to seriously reduce greenhouse gas emissions.

Of particular interest to outdoors people of every type are these two findings.

– Global climate is changing, and this is apparent across the U.S. in a wide range of observations. The climate change of the past 50 years is due primarily to human activities, predominantly the burning of fossil fuels.

U.S. average temperature has increased by about 1.5°F since 1895, with more than 80% of this increase occurring since 1980. The most recent decade was the nation’s warmest on record. Because human-induced warming is superimposed on a naturally varying climate, rising temperatures are not evenly distributed across the country or over time.

– Natural ecosystems are being directly affected by climate change, including changes in biodiversity and location of species. As a result, the capacity of ecosystems to moderate the consequences of disturbances such as droughts, floods, and severe storms is being diminished.

In addition to climate changes that directly affect habitats, events such as droughts, floods, wildfires, and pest outbreaks associated with climate change are already disrupting ecosystem structures and functions in a variety of direct and indirect ways. These changes limit the capacity of ecosystems such as forests, barrier beaches, coastal wetlands, and freshwater wetlands to adapt and continue to play important roles in reducing the impacts of these extreme events on infrastructure, human communities, and other valued resources.