Impact of Climate Change in Northwest USA

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Impacts of climate change narrow to three areas:
-erratic climate and weather extremes
-altered ecosystems and habitats
-risks to human health and society

Low snowpack prompts power concerns for utilities

Water supply is crucial for energy production, agriculture, and ecosystems in the northwest. Much of this region's supply is stored in winter snowpack in the mountains. The snowpack melts and runs off into streams and rivers in the late spring and summer, times where there is little rainfall. Climate change will threaten this natural storage.  Higher temperatures will contribute to earlier snowmelt and major changes in the timing of runoff. Changing stream flows would strain water management and worsen existing competition for water. Increasing temperatures and population could increase demand and further stress urban water supplies. *Climate change could decrease supply.*
Approximately 70% of electricity in the Northwest is powered by hydroelectricity. Decreasing summer streamflows would reduce hydroelectricity and stress electricity supplies. Meanwhile, rising temperatures would increase electricity demands for air conditioning and refrigeration.




Projected climate change impacts forests due to higher risks of forest fires. This will result in decreased tree growth and increased insect attacks. The potential reductions in summer soil moisture would contribute to wildfire risk. Drought stress and higher temperatures will impede tree growth, Projected climate changes will likely cause shifts in the composition, range and even existence of Northwest tree species. Decreasing supplies of water irrigation, increasing incidence of pests and disease attacks, and growing competition from weeds threaten Northwest agriculture, particularly the production of fruit trees.
Already known that human activities threaten salmon populations, climate change impacts would further stress these salmon population. Earlier peakflows and higher streamflows due to climate change would damage spawning nests and force young salmon from rivers prematurely.


Climate change, particularly sea level rising, is projected to increase coastal erosion and loss of beaches in the Northwest. Some climate models project that changing wind patterns, combined with sea levels rise could accelerate coastal erosion. Sea level rise could increase risk of landslide on coastal bluffs.



From forests fires and climate change, warmer polluted air affects the environment. A warmer atmosphere increases chemical reactions that form ground-level ozone, aka smog. Smog is a well-known lung irritant and a major trigger for asthma attacks.

Climate and Climate Controls in West USA

Precipitation of the Western United States varies spatially because of the scattered smaller-scale climactic controls placed within larger-scale controls. The distribution of seasonal precipitation shows complex patterns in some areas. Winter and spring precipitation currently supplies most of the water to metropolitan areas; the amounts are important for agriculture and for ski industry.  During the summer and fall, changes in precipitation are less critical. Small fluctuations of precipitation can affect local water budgets, erosion, and the growth of grasses important for cattle raising.
Oregon's Climate can be classified as mild. Two major geographic features dominate the climate in the state: the Pacific Ocean and the Cascade Range. The mountains of the Cascade Range act as a division between western and eastern sides of Oregon. An oceanic climate or "marine west coast climate" is predominantly found in Western Oregon, and a much drier climate prevails east of Cascade Range/east of Oregon.
Climate Controls are important to beach and property erosion, flood probabilities, and estuarine water quality.
Climograph, in Eugene Oregon

Hurricane Nora

Hurricane Nora was a third tropical cyclone that reached Arizona as a tropical storm.  Nora occurred in 1997 during the Pacific hurricane season. Hurricane Nora formed on September 16 and dissipated on the 26th. Nora formed over very warm water (29-30 degrees Celsius) Nora developed south of the Mexican coast, intensified into a hurricane, and made landfall over northwestern Mexico and the southwestern United States. A high pressure area over northern Mexico forced the storm to move west to northwest. During that period, Nora continued to intensify becoming a Category 1 hurricane. It's highest winds reached 130 mph (215km/h). Hurricane Nora affected Baja, California, and Southwest United States. In the United States, there were no direct deaths blamed on the hurricane. Although this is the case, the California Highway Patrol attributed three or four traffic fatalities in southern California due to weather.  Damage totals from Nora aren't fully discovered. The media summaries of Nora included a loss to agriculture estimated at several hundred millions; approximately $150-200 million (1997 USD).  It is also estimated that $30-40 million dollars in damage to lemon trees occurred. In California, about 125,000 customers lost power in the Los Angeles area with scattered, smaller outages elsewhere. In San Diego, Palm Springs, and Indio, street flooding was reported.

Hurricane Nora's remnants over the Southwestern
United States

Nora rainfall for Mexico and United States

West USA Air Mass

West USA has a Maritime Polar (mP) air mass; it's cool and moist.
Seasons in West USA vary.
The ones closest to us will have similar weather and season patterns. These places include Northern Arizona, Northern New Mexico, Southern Colorado, and Southern Utah. As previously stated, most high country Southwest USA seasons and weather are very similar. The desert areas like Southern Arizona, Southern New Mexico, and California have less distinctive seasons.
Spring and Fall weather for these places are more unpredictable. These times require inhabitants to be prepared as sudden changes are prevalent at these times of the year.

The Global wind that mainly impacts West USA is the prevailing westerlies. Most weather in the United States moves from West to East because of this.

Northwest USA (Oregon, Washington and Southern Alaska) will have orographic precipitation. These places are close to the sea; relief/orographic rainfall occurs when winds pick up moisture from sea as they travel across making the air most.  These places are commonly known for being wet, moist areas.
Southwest USA