Overview
Precipitation and temperature are primary factors that determine an ecosystem's structure and function. Secondary factors include long-term climate patterns, such as the timing, duration, and intensity of extreme weather events (such as frosts and violent downpours), and the variance in seasonal dynamics between and among years.
These drivers greatly influence which plant species occur where, habitat suitability for wildlife, surface and subsurface hydrology, how nutrients are cycled, and the relationships between soil, plants, and water availability. They can also affect how susceptible—or resilient—an ecosystem is to disturbance.
Perhaps no feature defines the Sonoran Desert more than its bimodal precipitation regime. Interspersed between the Mohave and Chihuahuan deserts, the Sonoran Desert receives the frequent low-intensity winter (December/January) rains of the former, as well as the violent summer (July/August) "monsoon" thunderstorms of the latter. These distinct rainy seasons support a broad array of warm- and cool-season flora and fauna, and are the primary cause of the amazing species and lifeform diversity of the Sonoran Desert. Winter precipitation occurs when a low-pressure trough develops over the western United States, pushing the prevailing Pacific storm tracks south over the Sonoran Desert.
Annual precipitation in the Sonoran Desert averages from 76 to 500 mm (3–20 in) depending on location, with substantial inter- and intra-annual variability in timing and quantity. Precipitation is typically much higher with elevation due to the orographic effects of the sky islands, with a sizable proportion occurring as snowfall.
The Sonoran is a hot desert. Summer air temperatures routinely exceed 40°C (104°F), and often reach 48°C (118°F). These high near-surface temperatures interact with cool, moist air in the atmosphere to produce the violent thunderstorms of the summer monsoons. As moisture on the soil surface and near-surface air evaporate following a storm, temperatures may drop 10°C (50°F) or more, often within a matter of minutes. Winter temperatures are mild, with valley bottoms typically free of frost, while the surrounding mountains may have dense snow cover at high elevations and north and east aspects. During any season, diurnal swings of 15°C (59°F) or more are common, as the dry atmosphere and relatively low vegetation cover facilitate re-radiation of daytime heat into the atmosphere overnight.
In the Sonoran Desert and Apache Highlands ecoregions, vast differences in aspect and topography make for a spatially variable climate. Understanding broad-scale weather and climate conditions is vital to park managers. Among other uses, it can help guide activities related to fire management and habitat protection; suggest the likelihood of exotic plant invasion, the availability of surface water, and the potential occurrence of plant die-offs and recruitment events; and indicate the potential success of disturbed lands restoration actions. It can also help the Sonoran Desert Network to understand changes in other vital signs.
Methods and Measurements
To obtain information on climate patterns, the network relies on The Climate Analyzer, an interactive website that allows users to create custom graphs and tables from historical and current weather-station data. For Sonoran Desert Network parks, users of The Climate Analyzer can investigate current and historical data related to the following parameters:
- air temperature
- precipitation
- potential evapotranspiration
- reconnaissance drought index
- discharge
- water temperature
- conductivity
The Climate Analyzer uses climate stations from throughout the region. To address data gaps, the Sonoran Desert Network also augments existing weather station networks with automated, real-time weather stations at selected locations. All network parks have at least one climate station used by The Climate Analyzer.
For more information, contact Kara Raymond, Hydrologist, Southern Arizona Office.
Quick Reads
Showing results 1-10 of 15
- Locations: Organ Pipe Cactus National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Sonoran Desert Network scientists monitor key resources and weather at Organ Pipe Cactus National Monument by taking measurements throughout the year, which helps us notice changes over time. This report summarizes weather, groundwater, and springs data from Water Year 2022. The data indicate the park's springs contained near-average levels of water, but high levels of several water chemistry parameters. WY2022 was warm and dry overall, with fewer cold days than average.
- Locations: Fort Bowie National Historic Site
- Offices: Sonoran Desert Inventory & Monitoring Network
Understanding changes in climate, groundwater, and surface water is key to assessing the condition of natural and cultural resources on national parks. At Fort Bowie National Historic Site we conduct long-term monitoring of climate, groundwater, and springs to provide early warning of potential problems, allowing managers to mitigate them before they become worse. In water year 2022, precipitation was boosted by an above average monsoon season.
- Locations: Tonto National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Sonoran Desert Network scientists monitor key resources and weather at Tonto National Monument by taking measurements throughout the year, which helps us track changes over time. This report summarizes weather and springs data from Water Year 2022. The data describe a dramatic change to Cave Canyon Spring. WY2022 was the third consecutive year of drought, and the park received less than average precipitation in all but three months.
- Locations: Saguaro National Park
- Offices: Sonoran Desert Inventory & Monitoring Network
Climate and water shape ecosystems and the services they provide, particularly in arid places like the Sonoran Desert. We monitor climate, groundwater, and 16 springs at the park to help managers protect park resources. Understanding how climate and water may be changing over time can also help explain changes in plants and animals on the park.
- Locations: Tumacácori National Historical Park
- Offices: Sonoran Desert Inventory & Monitoring Network
Sonoran Desert Network scientists monitor key resources and weather at Tumacácori National Historical Park by taking measurements throughout the year, which helps us notice changes over time. This report summarizes weather, groundwater, and springs data from Water Year 2022. The data indicate the park's groundwater is rising slightly. WY2022 was warm and wet overall, though most precipitation was due to three extreme months of rainfall making up for otherwise dry conditions.
- Locations: Gila Cliff Dwellings National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Sonoran Desert Network scientists monitor key resources and weather at Gila Cliff Dwellings National Monument by taking measurements throughout the year to understand changes over time. This report summarizes analyses of weather and springs data from Water Year 2022. The data indicate the park had a noteworthy heavy monsoon season, and the two monitored springs continue to be wet year-round. Air temperatures were similar to previous averages.
- Locations: Tuzigoot National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Sonoran Desert Network scientists monitor climate and water at Tuzigoot National Monument by taking measurements throughout the year. This report summarizes climate and springs data from Water Year 2022. Monitoring these key natural resources at the park helps us detect changes over time. The data indicate the park had a relatively dry year, though the spring was wet for all 173 days monitored. Maximum temperatures were warmer than previous averages.
- Locations: Casa Grande Ruins National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Sonoran Desert Network scientists take measurements of key resources at Casa Grande Ruins to understand how natural resources in the park may be changing over time. This report summarizes analyses of weather and groundwater data from water year 2022. The data indicate the park is in mild drought though groundwater levels remain stable. Temperatures were warmer than average. Ten months had below average rainfall, but two months experiencing extreme precipitation.
- Locations: Chiricahua National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
This report summarizes the Sonoran Desert Network’s analyses of weather, groundwater, and springs data from Water Year 2022 in Chiricahua National Monument. Monitoring these important natural resources at the park helps us understand changes over time. The data indicate the park had a heavy monsoon season and is not in drought, though most months had far below average precipitation. The groundwater was higher than in WY2021, though surface water springs show signs of drying.
- Locations: Montezuma Castle National Monument
- Offices: Inventory and Monitoring Division, Natural Resource Stewardship and Science Directorate, Sonoran Desert Inventory & Monitoring Network
At Montezuma Castle National Monument, the precontact built environment reflects the importance of reliable water sources. At this parks, the Sonoran Desert Network monitors climate, groundwater, and springs. Understanding changes in these closely linked factors helps managers make informed decisions affecting both natural and cultural resources. Learn about our findings for water year 2022.
Source: Data Store Saved Search 2570. To search for additional information, visit the Data Store.
Source: Data Store Collection 3858. To search for additional information, visit the Data Store.
Legacy briefs for climate and water monitoring are also available.
Last updated: June 13, 2024