Status of climate and water resources at Amistad National Recreation Area: Water year 2018
Raymond K, Palacios L, McIntyre C. 2019. Status of climate and water resources at Amistad National Recreation Area: Water year 2018. Natural Resource Report. NPS/CHDN/NRR—2019/2006. 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, groundwater, and springs is central to assessing the condition of park biota and key cultural resources. This report combines data collected on climate, groundwater, and surface water at Amistad National Recreation Area (NRA) to provide an integrated look at climate and water conditions during water year 2018 (October 2017 – September 2018). Overall annual precipitation was 92% of normal. Over half of the annual rainfall occurred in September. Eight of the other months were substantially drier than normal, receiving only 8 – 53% of normal rainfall. Mean minimum and maximum monthly temperatures were variable compared to the 30-year normal. Extremely warm days occurred 12% less frequently than normal, while there was 35% more extremely cold days. The reconnaissance drought index indicates that WY2018 was slightly drier than normal, following an overall wetter decade. The five-year moving mean of total annual precipitation demonstrates a surplus. Mean reservoir level in WY2018 was 1089.37 feet above mean sea level, 3.14 feet lower than the mean for WY2017, and 4.29 feet lower than the mean of 1990 – 2017. Of the six monitoring wells, water level in four wells increased by as much as 9.29 feet in WY2018 compared to WY2017, and water level in two wells decreased by as much as 5.34 feet. The historic record for three wells indicates that groundwater level has fluctuated with reservoir level. Data collection only began recently at the other three wells. Four springs were monitored at the recreation area. All had surface water and obligate/facultative wetland vegetation and three had invasive non-native plants present when visited in WY2018.
- Type
- Published Report
- Authors
- Raymond, Kara; Palacios, Laura; McIntyre, Cheryl
- Date of Issue
- 2019-09
- Publisher
- National Park Service
- Units
- AMIS , CHDN , NRSS
- Keywords
- climate, climate and water monitoring, water resources