Climate change is here.

That's the word from the US Global Change Research Program, which just released its third overview of climate change impacts and projections across the nation.

Broken down into regions, the National Climate Assessment offers some key messages for the Southwest, which includes 56 million people in Arizona, California, Colorado, Nevada, Utah and New Mexico:

  • Snowpack and streamflow amounts are projected to decline. This will affect cities, farms and ecosystems.
  • Irrigation-dependent farms are vulnerable to declining surface water supplies and crops are vulnerable to extremes of moisture, cold and heat. The report’s authors note that as temperatures and competition for water increase—and crop yields decrease—rural communities will lose jobs.
  • Thanks to warmer temperatures, drought and insect outbreaks, the region is already experiencing more wildfires. Between 1970 and 2003, the burn area of the West’s mid-elevation conifer forests—such as those in the Jemez Mountains—have increased by 650 percent. And between 1984 and 2008 wildfire and bark beetles killed trees across 20 percent of New Mexico and Arizona’s forests. And this is only the beginning: Models predict more wildfires and increased risk to Southwestern communities. 
  • The continued rise in regional temperatures will threaten public health in the region’s cities. The report’s authors add that “disruptions to urban electricity and water supplies will exacerbate these health problems.” Heat stress can kill people, especially elderly residents, but it also aggravates respiratory and heart problems.

Climate change also poses particular threats to the region's 182 American Indian tribes, as well as communities along the US-Mexico border. According to the report, "tribes may face loss of traditional foods, medicines and water supplies due to declining snowpack, increasing temperatures and increasing drought."

The report's authors also note that the lack of financial resources and low tax bases for tribal and border communities only exacerbates the problems they'll face as the impacts from climate change intensify. Already lacking adequate infrastructure—whether roads or for safe drinking water—those communities will be even more vulnerable to risks such as "air pollution, inadequate erosion and flood control and insufficient safe drinking water."

Development of the assessment was overseen by a 60-member Federal Advisory Committee established four years ago by the US Department of Commerce. Released in January 2013 the draft report was open to public comment and review by the National Academies—which released its consensus report last year.

In other words, this is a serious report that has been held to the highest peer-review standards. Its findings can't easily be debunked by a few doubters calling climate change a hoax.

The assessment's website is user-friendly to navigate, whether you're seeking to browse impacts by regions, response strategies or sectors, such as water, energy, transportation, agriculture, and human health. Many of the references cited also link to original research articles for people looking for more information on everything from wildfire to greenhouse gas emission reduction strategies.

Check out the entire report  and read the Southwest region section yourself.

And maybe? Pass the word on to elected officials in the state—the most imaginative of whom deny human-caused climate change, the me

ekest just choose to ignore it.