NOAA releases climate assessment framework, including statewide information
The National Oceanic and Atmospheric Administration (NOAA) recently updated their state-specific climate summaries after the demand for state-level information increased with the release of the Third National Climate Assessment.
NOAA said, “These summaries cover assessment topics directly related to NOAA’s mission, specifically historical climate variations and trends, future climate model projections of climate conditions during the 21st century and past and future conditions of sea level and coastal flooding.”
NOAA began by explaining the factors affecting Wyoming’s overall climate.
“Wyoming’s climate is determined, to a large extent, by its location in the middle latitudes, in frequent close proximity to the jet stream and in the interior of the North American continent, far from oceanic moisture sources,” they explained.
The proximity to jet streams brings frequent storms but a lack of moisture, resulting in a semi-arid climate.
“It has large climatic variations due to its geographic diversity and altitudinal range,” NOAA said of the state.
A range of elevation from 3,100 feet to 13,800 feet and a similar variation in temperature is also seen.
NOAA identified three key messages for each state, noting that temperature increases, precipitation increases and evaporation increases will all have impacts in the state in the future.
“Average annual temperature has increased approximately 1.4 degree Fahrenheit since the early 20th century,” NOAA remarked. “This increase is most evident in winter warming, which has been characterized by a below average occurrence of very cold days since 2000.”
They added, “Under a higher emissions pathway, historically unprecedented warming is projected by the end of the 21st century.”
Next, they noted that increases are projected for both spring and winter precipitation, which will include a shift from rainfall to snowfall in the spring. The result could increase flood potential.
Finally, NOAA said, “Higher temperatures will increase evaporation rate and decrease soil moisture, leading to more intense future droughts.”
The impact will be an increase in the occurrence and severity of wildfires in Wyoming, according to NOAA.
As a key point of their analysis, NOAA mentioned, “Wyoming serves as a major source of water for other states, and changes in precipitation can have broad impacts beyond the state’s boundaries.”
Water from the state flow into the Missouri-Mississippi river basin, the Green-Colorado river basin, the Snake-Columbia river basin and the Great Salt Lake river basin.
Variation in snowpack affects water availability across the West, as well.
“In years with heavy snow cover, heavy rains during the spring thaw can cause severe flooding by causing rapid melting of the snowpack,” they added.
Additionally, the state is susceptible to drought – a fact well known by most in the ag industry.
“From 1999 to 2008, large portions of the state experienced drought,” NOAA said, mentioning that 2012 was Wyoming’s driest year since 1895. “By October 2012, almost 90 percent of the state was in severe drought.”
When coupled with hot temperatures and high wind, wildfires were rampant.
From their research, NOAA noted that spring and winter precipitation are projected to increase between five and 15 percent across the state.
“This will increase the likelihood that some of the precipitation events now occurring as snow will fall as rain instead, reducing water storage in the snowpack, particularly at lower elevations,” NOAA said.
An earlier melting snowpack means that summer months would likely be drier, as well as an increased potential for flooding.
Future droughts are also projected to be more severe.
“Even if precipitation amount increase in the future, rises in temperature will increase evaporation rates, resulting in a decreased rate of loss of soil moisture during dry spells,” NOAA noted.
Saige Albert is managing editor of the Wyoming Livestock Roundup and can be reached at firstname.lastname@example.org.