Status of climate and water resources at Casa Grande Ruins National Monument: Water year 2018
Raymond K. 2019. Status of climate and water resources at Casa Grande Ruins National Monument: Water year 2018. Natural Resource Report. NPS/SODN/NRR—2019/1940. National Park Service. Fort Collins, Colorado
Climate and hydrology are major drivers of ecosystems. They dramatically shape ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate and groundwater is central to assessing the condition of park biota and key cultural resources. This report combines data collected on climate with an overview of groundwater resources at Casa Grande Ruins National Monument (NM) for water year 2018 (October 2017–September 2018). Air temperatures at Casa Grande Ruins NM tended to be warmer than normal, especially in the fall and winter months, and there were substantially fewer extremely cold days. Annual precipitation was only 63% of normal (5.81" vs. 9.18") in WY2018 when compared to normalized climate data for 1981–2010. Monsoon rainfall was greater than normal, but the rest of the year was substantially drier. A single, 0.65" storm event in June dropped 1,300% of that month’s normal rainfall. The reconnaissance drought index indicated that the regional drought that began in 2000 continued through WY2018. Groundwater levels near Casa Grande Ruins in WY2018 increased 12.3 feet from WY2017, a deviation from the general downward trend since 1995. Irrigation districts in the Eloy basin near the Central Arizona Project canal began receiving water in 1987. However, the San Carlos Irrigation District, adjacent to the park, is outside the Central Arizona Project service area, and groundwater levels have generally declined. Land subsidence at Casa Grande Ruins NM between March 2017 and March 2018 was 0–1 centimeters in most of the park, and up to 2 centimeters in the park’s northwest corner.
- Type
- Published Report
- Authors
- Raymond, Kara
- Date of Issue
- 2019-06
- Publisher
- National Park Service
- Units
- CAGR , NRSS , SODN
- Keywords
- Casa Grande Ruins National Monument, climate, groundwater, monitoring, Sonoran Desert Network
- Subjects
- Ecological Framework: Air and Climate | Weather and Climate | Weather and Climate , Ecological Framework: Water | Hydrology | Groundwater Dynamics