Report on the observed climate, projected climate, and projected biodiversity changes for Aransas National Wildlife Refuge, Texas, U.S. under differing levels of warming

Jeff Price, Nicole Forstenhäusler, Erin Graham, Timothy J. Osborn, Rachel Warren

Research output: Book/ReportOther report


Aransas National Wildlife Refuge is among the top 27% of all non-marine protected areas, globally. This refuge is projected to be largely resilient to climate change with warming to 2°C. With 3°C of warming and above the resiliency drops to the point that business as usual conservation will likely be insufficient. Averaged over the entire area of the refuge, with 4°C warming (global, above pre-industrial), the area is projected to remain climatically suitable for 64.6% of its terrestrial biodiversity (fungi, plants, invertebrates, and vertebrates), with none of its area remaining an overall refugia (remaining climatically suitable for >75% of the species) for biodiversity. If warming levels were held to 2°C, 55.3% of the area would remain a climatic refugia and the area would remain climatically suitable for 81.8% of its terrestrial biodiversity.
Between 1961-1990 and 1991-2020 the average monthly temperature has increased by 0.1° - 1.5°C. With warming levels of 2.0°C the new average monthly temperature is equivalent to that only seen 1 in 3 years in 1961-1990 for March -October (up to 1 in 20 years for June - August). Half of the months have become wetter and the rest (February, May-September) drier. Models project that most months will become drier (except for June and September). The number of months classified as in severe drought have increased substantially between 1961-1990 and 1986-2015. With warming levels of 2°C (global, relative to pre-industrial) the number of months in severe drought is projected to be double that of 1986-2015 with the possibility of droughts lasting 1-2 years.
Biodiversity adaptation options will largely allow for business-as-usual conservation taking into account changes in extreme events (heat and severe drought) up to 2°C warming. Typical resilience measures such as removing other stressors will be critical. At higher warming levels, increasingly complex adaptation measures will be required.
These reports do not include the projected impacts of sea level rise, and this will have large impacts on parts of the refuge. The general topography allows for potential migration of the saltmarsh inland. While many of the sea level rise impacts are already ‘locked in’, the timing is less certain.
Original languageEnglish
Number of pages51
Publication statusPublished - 11 Jun 2024


  • protected areas, biodiversity, climate change

Cite this