Extreme Weather

Residents living along the coast of Lake Ontario and the St. Lawrence River have experienced two record-setting floods, one in 2017 and another in 2019. These floods caused tremendous property damage and disruptions to the regional economy. The water levels on Lake Ontario are influenced by the operations of the Moses Saunders Dam on the St. Lawrence River. These operations are determined by the I

Freshwater is a critical driver for island ecosystems. Climate change has fundamentally altered the water cycle in tropical islands. The changes in dynamic patterns of streamflow could result in the temporal and spatial difference in the riverine, estuarine, and coastal habitats that support native species. In particular, these habitats support the nine native aquatic species in Hawaiʻi at differe

Drought and wildfire pose enormous threats to the integrity of natural resources that land managers are charged with protecting. Recent observations and modeling forecasts indicate that these stressors will likely produce catastrophic ecosystem transformations, or abrupt changes in the condition of plants, wildlife, and their habitats, in regions across the country in coming decades. In this p

Detailed, reliable projections of future changes in climate are needed by Hawai‘i’s resource managers, such as water utilities managers, land managers, conservation organizations, and decision makers. However, global climate models (or “general circulation models”), which are currently the most commonly used tool for projecting future climate variations, are known for representing large-scale clim

American Samoa is vulnerable to sea-level rise in part due to the steep terrain of its islands. This terrain requires the majority of the islands’ villages and infrastructure to be located along thin strips of coastal land. The situation is worsened by the recently recognized rapid sinking of the islands, which was triggered by the 2009 Samoa earthquake and is predicted to last for decades. This s

Changing climate in the “Ridge-to-Reef" (R2R) and “Icefield-to-Ocean" (I2O) ecosystems of Hawai‘i and Southeast Alaska is expected to influence freshwater resources, extreme precipitation events, intensity of storms, and drought. Changes in these regions will not be uniform, rather they will depend on elevation and watershed location due to their steep-gradient terrains. A better understanding of

Freshwater mussels are an important component of freshwater ecosystems. They can filter a large amount of water, affecting both water clarity and water chemistry. Their shells provide physical habitat for other organisms, they re-direct necessary nutrients to the bottom of the water column, and their excreted material can enhance the growth of algae and macroinvertebrates. However, dramatic declin

Some areas of the U.S. Affiliated Pacific Islands (USAPI) are experiencing a decline in precipitation and streamflow and an increase in the number of severe droughts. These changes can have wide-reaching implications, affecting the water supply, native vegetation and wildlife, wildfire patterns, and the spread of invasive species. As ecosystems become altered by invasive species and as particularl

Sea-level rise will eventually flood and kill many coastal mangrove trees. The loss of mangrove forests will strongly affect human populations on isolated western Pacific islands as they rely heavily on mangroves for food, such as fish, shrimp, and crabs; building materials; and fire wood. Mangroves also shelter coastal communities from the impacts of tsunamis and cyclones, are home to endangered

The Pacific Ocean is home to a number of low-lying, coastal national parks and wildlife refuges. These public lands are situated on coral reef-lined islands that are susceptible to inundation from sea-level rise and flooding during storms. Because of their low-lying nature and limited availability of space, ecosystems, cultural resources, and infrastructure on these islands are particularly vulner

The threat of rising sea levels to island communities is well known. However, sea-level rise projections are often depicted in ways that are not intuitive or directly applicable to community members and resource managers who most need the information. Scientific information about sea-level rise needs to be presented in a way that effectively communicates the very real risk posed to coastal commun

The Rio Grande is naturally a water-scarce basin in which droughts have been classified as severe (with almost no rain during some years) and extended (lasting more than 10, or even 15 years). Severe and persistent droughts in the Rio Grande basin reduce water availability, which triggers economic, environmental, and social impacts, and affects compliance with interstate compacts and international