User:Nilmariliz/Climate change in Arizona

Climate change in Arizona

From Wikipedia, the free encyclopedia Jump to navigationJump to searchKöppen climate types in Arizona show a preponderance of arid and desert environments.

Climate change in Arizona encompasses the effects of climate change, attributed to man-made increases in atmospheric carbon dioxide, in the U.S. state of Arizona.

Arizona is largely a semi-arid desert receiving only 20.4 cm of rain across only 36 d per year on average and with an average yearly temperature of 24 °C (US Climate Data 2016). It has been asserted that Arizona "will suffer more than most of U.S." due to climate change. According to the United States Environmental Protection Agency, Arizona "has warmed about two degrees (F) in the last century. Throughout the southwestern United States, heat waves are becoming more common, and snow is melting earlier in spring. In the coming decades, climate change is likely to decrease the flow of water in the Colorado River, threaten the health of livestock, increase the frequency and intensity of wildfires, and convert some rangelands to desert". Climate change has not only caused superficial damage. It has caused environmental problems that have affected Arizona's agriculture and production, thus harming its economy and the development of basic human needs such as water and food. It has put many animals in danger of extinction and those that are not yet endangered species, are affected in their diet, ecosystems and environments. Also, climate change has caused social problems showing its effect in various tribal communities in Arizona.

Contents

• 1Environmental impacts
  • 1.1Snowpack
  • 1.2Water availability
  • 1.3Wildfires and changing landscapes
  • 1.4Pests
• 2Economic and social impacts
  • 2.1Agriculture
  • 2.2Endangered Species
  • 2.3Tribal communities
• 3See also
• 4References
• 5Further reading

Environmental impacts[edit]

Snowpack[edit]

A snowpack is "a seasonal accumulation of slow-melting packed snow".Snowpack data is valuable for monitoring the effects of climate change. Snowmelt is an important water source that keeps streams flowing in the warmer months. It is also an important water source for humans, replenishing reservoirs. "As the climate warms, less precipitation falls as snow, and more snow melts during the winter, decreasing snowpack. Since the 1950s, the snowpack has been decreasing in Arizona, as well as most mountainous areas in the Colorado River Basin. Diminishing snowpack can decrease water supplies and shorten the season for skiing and other forms of winter tourism and recreation".

Water availability[edit]

"The changing climate is likely to increase the need for water but reduce the supply. Rising temperatures increase the rate at which water evaporates (or transpires) into the air from soils, plants, and surface waters. Irrigated farmland would thus need more water. But less water is likely to be available, because precipitation is unlikely to increase enough to make up for the additional water lost to evaporation. Annual precipitation has decreased in Arizona during the last century, and it may continue to decrease. So soils are likely to be drier, and periods without rain are likely to become longer, making droughts more severe".

"The decline in snowpack could further limit the supply of water for some purposes. Mountain snowpack are natural reservoirs. They collect the snow that falls during winter and release water when the snow melts during spring and summer. Over the past 50 years, the snowpack throughout the Colorado River Basin has been melting earlier in the year (see map on back page). Dams capture most meltwater and retain it for use later in the year. But upstream of these reservoirs, less water is available during droughts for ecosystems, fish, water-based recreation, and landowners who draw water directly from a flowing river".

Wildfire

Wildfires and changing landscapes[edit]

A wildfire is "a sweeping and destructive conflagration especially in a wilderness or a rural area". Long-term antecedent climate conditions are often overlooked as important drivers of wildfire variability. "Higher temperatures and drought are likely to increase the severity, frequency, and extent of wildfires, which could harm property, livelihoods, and human health. On average, more than 2 percent of the land in Arizona has burned per decade since 1984. Wildfire smoke can reduce air quality and increase medical visits for chest pains, respiratory problems, and heart problems".

"The combination of more fires and drier conditions may expand deserts and otherwise change parts of Arizona’s landscape. Many plants and animals living in arid lands are already near the limits of what they can tolerate. A warmer and drier climate would generally extend the Sonoran and Chihuahuan deserts to higher elevations and expand their geographic ranges. In some cases, native vegetation may persist and delay or prevent expansion of the desert. In other cases, fires or livestock grazing may accelerate the conversion of grassland to desert in response to a changing climate. For similar reasons, some forests may change to desert or grassland".

Desert tortoise

Pronghorn antelope

Endangered Species

Some of the Arizona species on the endangered list are the Sonoran pronghorn antelope, the Mexican gray wolf, the desert nesting bald eagle, the southwestern willow flycatcher and several fish species native to the Gila River basin. The Sonoran pronghorn was the most vulnerable to climate change of the species scored. Drought was the main reason listed for the species facing harm from climate change. Also there are some endangered species that can manage to survive the intense heat but not with the lost of their habitats. For example, the desert tortoise thrives in intense heat and can go a year without water, but it’s among the species threatened by climate change, it would be harmed by changes in the vegetation it relies on for food as well as stress from drought, heat, fire and other problems created by warming temperatures. It is vulnerable to loss of habitat, including loss of cactus, an important food and water source, and shrubs that provide shade. Increases in invasive grasses and frequency of fires will accelerate habitat change.

Economic and social impacts[edit]

Pests[edit]

"Warmer and drier conditions make forests more susceptible to pests. These "are insects or small animals which damage crops or food supplies" affecting agriculture. Drought reduces the ability of trees to mount a defense against attacks from pests such as bark beetles, which have infested 100,000 acres in Arizona. Temperature controls the life cycle and winter mortality rates of many pests. With higher winter temperatures, some pests can persist year-round, and new pests and diseases may become established". Some of the most common pests in Arizona are termites, ants, cockroaches, tarantulas and other spiders, scorpions, ticks, bees and wasps, and bed bugs.

Agriculture[edit]

Climate change is expected to impact runoff and soil erosion on rangelands. It already has significant negative impacts on agriculture in the United States, causing substantial economic costs (Backlund et al 2008) and raising serious questions about the vulnerability of food supply chain. Arizona is a major agricultural producer, supplying considerable animal feed, livestock, milled grain products, meat, and other food products to cities throughout the US.Disruptions to its agricultural production could be caused by failures in energy or water systems, or by the effects of temperature change on crop characteristics. "Interdependent systems providing water and energy services are necessary for Arizona's agriculture. Climate change and increased resource demands are expected to cause frequent and severe strains on these systems. Arizona is especially vulnerable to such strains due to its hot and arid climate". "Increasing droughts and higher temperatures are likely to affect Arizona's top agricultural products: cattle, dairy, and vegetables. Hot temperatures threaten cows’ health and cause them to eat less, grow more slowly, and produce less milk. Livestock operations could also be impaired by fire, the lack of water, and changes in the landscape from grassland to woody shrubs more typical of a desert. Reduced availability of water would also create challenges for irrigated farms, which account for two-thirds of the water used in the state".

Tribal communities[edit]

"Climate change threatens natural resources and public health of tribal communities. Rising temperatures and increasing droughts are likely to decrease the availability of certain fish, hunt, and wild plants on which the Navajo and other tribes have relied for generations. Water may be less available for domestic consumption, especially for those who are not served by either municipal systems or reliable wells, which includes about 30 percent of the people on the Navajo Nation, who must haul water to meet daily needs. Recurring drought and rising temperatures may degrade the land itself. In the Navajo Nation, for example, the Great Falls Dune Field has advanced almost a mile in the last 60 years, threatening roads, homes, and grazing areas. Extreme heat may also create health problems for those without electricity, including about 40 percent of the people on the Navajo reservation".

See also[edit]

• List of U.S. states and territories by carbon dioxide emissions

References[edit]

1. ^
2. ^ Jump up to:^{a b c d e f g h i}

Further reading[edit]

• —this chapter of the National Climate Assessment covers Arizona, California, Colorado, New Mexico, Nevada, and Utah