Urban

Urban strategies and approaches.

Taxonomy Machine Name
niacs_strategy_urban
Taxonomy Alias
urban

Climate change will amplify many existing stressors to forest ecosystems in the Great Plains, such as invasive species, insect pests and pathogens, and disturbance regimes

Submitted by dshannon on

Forest ecosystems throughout the Great Plains are exposed to a range of natural, introduced, and anthropogenic stressors. High-elevation forests and semiarid riparian forests are faced with their own distinct kinds of stressors. Invasive plants, forest pests, diseases, droughts, and floods are expected to become more damaging under climate change, and these factors may interact in unpredictable ways.

Longer growing seasons, warmer temperatures, and greater water demand for agriculture may reduce available water for natural ecosystems.

Submitted by dshannon on

Water is central to the region’s productivity. Projected increases in winter and spring precipitation in the Northern Plains may benefit productivity by increasing water availability through soil moisture reserves during the early growing season. The Northern Plains will remain vulnerable to periodic drought because much of the projected increase in precipitation is expected to occur in the cooler months while increasing temperatures will result in additional evapotranspiration.

The freeze-free season is expected to increase by 15 to 33 days in the Northern Great Plains by the middle of the century.

Submitted by dshannon on

The freeze-free season is defined as the period of time between the last spring frost (daily minimum temperature below 32 degrees F) and the first fall frost. The length of the annual freeze-free season has been increasing since the 1980s, and all climate models agree that it will continue to increase in the future. The largest increases are projected for the high country of Wyoming and Montana.

A majority of climate models suggest that precipitation in the Northern Great Plains will increase in the winter, spring, and fall by the end of the century, but most models project that summer precipitation may decrease.

Submitted by dshannon on

The largest decrease (10-15%) in summer precipitation is expected in western Wyoming. The means of several climate models indicate that spring precipitation may increase around 3% across much of the Northern Great Plains by the middle of the century. Winter precipitation is expected to increase 6-12%, with larger increases expected in parts of the Dakotas. Under mild climate scenarios, changes are generally smaller than in more extreme climate scenarios.

The number of days per year with more than 1 inch of precipitation will increase across the Northern Great Plains by the middle of the century.

Submitted by dshannon on

Most of the region is projected to experience 0 to 45% more days each year with more than an inch of precipitation by the middle of the century. An increase in heavy precipitation events is expected for much of the region, other than high mountain areas in the southwestern area. By 2050, the frequency of two-day heavy rainfall events is expected to increase by 50%. The amount of rain falling in heavy, one-day events is expected to increase by 8-10% by mid-century. Days with more than 2 inches, 3 inches, and 4 inches of precipitation are also expected to occur more regularly.

Precipitation in winter and spring is expected to increase 10%–30% by the end of this century. Summer precipitation is expected to vary, ranging from no change under a low emissions scenario to a 10%–20% reduction.

Submitted by dshannon on

There is uncertainty between different climate scenarios for future precipitation projections in the Great Plains. Generally, there is a south-to-north gradient in annual precipitation projections, with increases projected north of the Nebraska-South Dakota border. However, annual precipitation and streamflow projections show only modest changes. The region already experiences considerable variability in precipitation each year, which contributes to a higher degree of uncertainity about future potential for flooding and drought.

The incidence of wildfire has been on the rise in the Great Plains; changing climate conditions may increase wildfire risks in the region by the end of the century.

Submitted by dshannon on

Different modeling approaches generally conclude that future climate conditions will increase the risk of wildfire across the Great Plains. Annual fire probability, calculated solely with climate data and physical principles, is projected to increase by 20% to 1200% across the region by the end of the century, with the largest increases occuring in Wyoming and western Montana.

There are projected to be many fewer cool days (days with minimum temperatures less than 28°F), with decreases of 30 days or more per year by mid-century.

Submitted by dshannon on

The largest decreases in number of cool days are expected in western areas of Montana and Wyoming, with much of this area expecting 35-50 fewer days with a minimum temperature below 28 degrees by the middle of the century. Nebraska and the Dakotas are expected to experience 20-30 fewer cool days.

By the middle of the century, the Northern Great Plains region is expected to experience between 5 and 45 more days per year with a maximum temperature exceeding 90 degrees Fahrenheit.

Submitted by dshannon on

For an average of seven days per year, maximum temperatures reach about 95 degrees F in the Northern Plains. By mid-century, much of the region is expected to experience 20-40 more hot days (above 90 degrees F) each year. The southern parts of this region, particularly Nebraska and South Dakota, will experience the largest increase in number of days above 90 degrees F, while mountainous portions of Wyoming and Montana will experience the least.

Temperatures in the Northern Great Plains are projected to increase by 3.5 to 9.5 degrees Fahrenheit between the years 2036-2100.

Submitted by dshannon on

All climate models agree that temperatures are projected to increase over the 21st century across the Northern Great Plains, with almost uniform temperature increases across the entire region. In winter, the greatest warming is expected in the northeastern part of this region, mainly in the Dakotas. Springtime warming is generally smaller than that of other seasons. Summer shows a large amount of warming, with the greatest increases in the southern part of the region, particularly in Nebraska and Wyoming.