Geology topics

Brooke C. Stewart

Publications and source records attributed to Brooke C. Stewart.

3 recordsLinked to original sources

USGS2020

North Carolina State climate report

Our scientific understanding of the climate system strongly supports the conclusion that North Carolina’s climate has changed in recent decades and the expectation that large changes—much larger than at any time in the state’s history—will occur if current trends in greenhouse gas concentrations continue. Even under a scenario where emissions peak around 2050 and decline thereafter, North Carolina will experience substantial changes in climate. The projected changes with the highest level of scientific confidence include increases in temperature, increases in summer absolute humidity, increases in sea level, and increases in extreme precipitation. It is also likely that there will be increases in the intensity of the strongest hurricanes. A full appreciation for past and future changes in North Carolina’s climate requires a global perspective. Earth’s climate has warmed substantially since the late 19th century, with most of that warming occurring in the last 50 years. This warming trend is clear from global temperature records and many other indicators, including rising global sea levels and rapid decreases in arctic sea ice cover. Scientists have very high confidence that this warming is largely due to human activities that have significantly increased atmospheric concentrations of carbon dioxide (CO2) and other greenhouse gases. Exhaustive research has examined other potential causes of this warming, and the increase in greenhouse gas concentrations is the only plausible cause that is consistent with the observed data and the physics that governs the climate system.

North Carolina↗

USGS2018

Puerto Rico and the U.S. Virgin Islands

Average annual temperature for Puerto Rico and the U.S. Virgin Islands has increased by more than 1.5°F since 1950. Under a higher emissions pathway, historically unprecedented warming is projected by the end of the 21st century, including increases in extreme heat events. Future changes in total precipitation are uncertain, but extreme precipitation is projected to increase, with associated increases in the intensity and frequency of flooding. Sea level has risen by 0.6 inches per decade at San Juan, Puerto Rico since 1961, near the global sea level rise rate during the second half of the 20th century. Global sea level rise projections range from 1 to 8 feet by 2100, with similar rises projected for Puerto Rico and the U.S. Virgin Islands. Rising sea levels pose widespread and continuing threats to both natural and built environments in coastal communities. Hurricanes are a major threat to both Puerto Rico and the U.S. Virgin Islands. Hurricane rainfall rates, storm surge heights due to sea level rise, and the number of the strongest (Category 3, 4, and 5) hurricanes are all projected to increase in a warming climate.

NOAA State Climate Summaries↗

USGS2013

Monitoring and understanding changes in heat waves, cold waves, floods, and droughts in the United States: State of knowledge

Weather and climate extremes have been varying and changing on many different time scales. In recent decades, heat waves have generally become more frequent across the United States, while cold waves have been decreasing. While this is in keeping with expectations in a warming climate, it turns out that decadal variations in the number of U.S. heat and cold waves do not correlate well with the observed U.S. warming during the last century. Annual peak flow data reveal that river flooding trends on the century scale do not show uniform changes across the country. While flood magnitudes in the Southwest have been decreasing, flood magnitudes in the Northeast and north-central United States have been increasing. Confounding the analysis of trends in river flooding is multiyear and even multidecadal variability likely caused by both large-scale atmospheric circulation changes and basin-scale “memory” in the form of soil moisture. Droughts also have long-term trends as well as multiyear and decadal variability. Instrumental data indicate that the Dust Bowl of the 1930s and the drought in the 1950s were the most significant twentieth-century droughts in the United States, while tree ring data indicate that the megadroughts over the twelfth century exceeded anything in the twentieth century in both spatial extent and duration. The state of knowledge of the factors that cause heat waves, cold waves, floods, and drought to change is fairly good with heat waves being the best understood.

Bulletin of the American Meteorological Society↗