Colorado got headlines when a massive and devastating Black Forest wildfire near Colorado Springs killed 2 people and destroyed 473 homes as the blaze moved through 25 square miles of forest and woodland neighborhoods. Thirty eight thousand people has been evacuated.
It has been the most destructive fire in Colorado’s history but firefighters are beginning to handle it.
“Understanding how climate has changed, how it is likely to change in the future, and what this means for water, wildfire, ecosystems, species, and people requires complex interdisciplinary study. It also requires an understanding of uncertainty, as projections of the future, even if they are based on the best data and expert modeling available, should not be treated as “for certain” forecasts. Instead, scientists and policy makers rely on a suite of global circulation (GCM) models, each with its strengths and weaknesses, to develop plausible scenarios for our future.” reads an article in the Mountain Studies Institute (MSI) of San Juan Mountains Institute of Colorado.
“Today, western forests are experiencing longer wildfire seasons and more acres burned compared to several decades ago, says Todd Sanford, a climate scientist at the Union of Concerned Scientists (UCS). The greatest increase has occurred in mid-elevation Northern Rockies forests, which are having higher spring and summer temperatures and earlier snow melt. These conditions are linked to climate change. In general, climate change is increasing the risk for longer wildfire seasons and more area burned,” he says.
Wildfires in the Western US has been increasing in frequency and duration, burning 6 times the area of land and lasting about 5 times longer, says their report.
“As the climate warms, moisture and precipitation levels are changing, with wet areas becoming wetter and dry areas becoming drier, the organization reports. Higher spring and summer temperatures and earlier spring snow-melt typically cause soils to be drier for longer, increasing the likelihood of drought and a longer wildfire season, particularly in the western United States. These hot, dry conditions also increase the likelihood that, once wildfires are started by lightning strikes or human error, they will be more intense and long-burning.”
This is the climate change summary released by the MSI:
-Southwestern Colorado has warmed about 2° F in the last three decades (i.e., 1977 to 2007). This rate of warming is the same as for Western Colorado, but greater than the Western US, or any other region of the US except Alaska.
-Temperatures are likely to increase by an additional 1.5 to 3.5 °F by 2025 and 2.5 to 5.5 °F by 2050.
-Summers are projected to warm more than winters. By 2050, typical average monthly temperatures in the summer are projected to be as warm as or warmer than the hottest 10% of summers from 1950 to 1999.
-The climate of the mountains is projected to migrate upward in elevation and the climate of the Desert Southwest to progress up into the valleys.
-Examples of Potential Impacts:
-Changes in agricultural crop production and spread of agricultural pests.
-Earlier snow melt and timing of peak river flows.
-Increased energy usage for heating and cooling.
-Increased heat-related illnesses and spread of disease.
-More amenity-led migration to the mountains from desert communities.
Evaporation and Evapotranspiration
-Due to increased temperatures, the rate at which water is evaporated from water bodies, soil, and vegetation is very likely to increase.
-This will make the environment drier even if precipitation stays the same.
-Examples of Potential Impacts
-Decrease in stream flow and water stored in reservoirs, especially in hot, dry years.
-Decreased soil moisture for crops and natural vegetation.
-Increased irrigation needs or shifts to more drought-resistant crops.
-Shifts in elevation ranges of plants and animals.
-Increased wildfire occurrence and forest die-offs.
-The San Juan Mountain region is difficult to model for precipitation due to complex topography and natural variability in precipitation patterns.
-Projections of change in amounts of precipitation for the region are not in consensus. Some studies indicate that annual precipitation will decrease slightly while others project an increase in the winter.
-Some models project more variable precipitation patterns with more frequent extreme events.
-Examples of Potential Impacts:
-Increased storm events and severity.
-Change in aquatic habitat.
Snowpack and Streamflow
-Warming temperatures are projected to have significant effects on snowpack, timing of snow melt, and stream flow even without a decrease in precipitation.
-It is likely that in the future more precipitation will fall as snow, snow packs will decrease and melt earlier, and peak stream flow will occur earlier in the spring.
-From 1978 to 2004, snow melt already shifted about two weeks earlier in Western Colorado. Snowbelt has shifted even earlier in the Pacific Northwest and Northern California, however.
-Decreases in the amount of water contained in snow packs are projected to be greater at elevations below 8,200 feet (i.e., a 20 to 60% reduction of snow pack by the period 2040 to 2069). Above 8,200 feet, the snow pack is anticipated to decrease by 10 to 20%.
-Examples of Potential Impacts
-More flooding in the spring.
-Reduced water availability in the summer.
-Shorter seasons for ski/snow and white water recreation industries.
-Increased summer recreation and tourism opportunities.
Colorado is suffering because of shifting temperatures: “On average, wildfires burn twice as many acres each year as compared to 40 years ago. Last year, the fires were massive in size, coinciding with increased temperatures and early snow melt in the West,”US Forest Service Chief Tom Tidwell told the Senate Energy and Natural Resources Committee in testimony last week. “The largest issue we now face is how to adapt our management to anticipate climate change impacts and to mitigate their potential effects.”
Costs of fire suppression have increased to consume nearly half of the entire Forest Service budget. “Despite some relief earlier this year, right now we’re seeing how quickly our weather can get hot and dry, creating hazardous fire and drought conditions,” Sen. Bennet said.
Written by Edgar Soto