Water, Coasts and Ice

Freshwater is a critical driver for island ecosystems. In Hawaiʻi, though rainfall intensity has increased, total rainfall has been on the decline for the last two decades and, as a result, streamflow has also been reduced. The changes in dynamic patterns of streamflow could result in impacts to river, estuarine, and coastal habitats. In turn, these changes also affect the nine native...

As freshwater streams and native fish are threatened by changing environmental conditions, efforts to coalesce existing data and integrate modeling and projection tools are increasingly necessary for informing effective land, water, and species management. For example, identifying and integrating disparate datasets of streamflow, stream water temperature and species distribution is...

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...

As a low-lying coastal nation, the Republic of the Marshall Islands is at the forefront of exposure to climate change impacts. The Republic of the Marshall Islands has a strong dependence on natural resources and biodiversity not only for food and income but also for culture and livelihood. However, these resources are threatened by rising sea levels and associated coastal hazards (storm...

The fast pace of change in coastal zones, the trillions of dollars of investment in human communities in coastal areas, and the myriad of ecosystem services natural coastal environments provide makes managing climate-related risks along coasts a massive challenge for all of the U.S. coastal states and territories. Answering questions about both the costs and the benefits of alternative...

The Republic of Palau, a Freely Associated State of the U.S. and a global leader in ocean conservation, recently implemented the Palau National Marine Sanctuary, which closed 80% of its ocean to fishing. As offshore fish become scarcer in the domestic market, managers have begun to worry about increased harvesting pressure on already overfished nearshore environments. This pressure, in...

Freshwater ecosystems support the health and well-being of human life and society through a myriad of services. Intact freshwater biodiversity maintains the health of freshwater ecosystems and the benefits they provide. However, staggering rates of freshwater biodiversity loss and declining ecological function of freshwater ecosystems threaten these natural benefits and human life. This...

Nearshore marine ecosystems in Alaska and Hawai‘i rely heavily on organic materials and nutrients delivered by rivers and streams. It is hypothesized that the magnitude and timing of stream flows influences this delivery of materials to coastal ecosystems. However, despite previous research on the topic, there is still considerable uncertainty about how stream flow may influence these...

Globally, shorelines provide a vital defense system against extreme weather and erosion events and are a critical public and cultural resource. Within the state of Hawaiʻi, coastal vulnerability and historic change has been well documented and studied on the Islands of Oʻahu, Maui, and Kauaʻi, but this has not been done for the Island of Hawaiʻi, the largest and most diverse island in...

Coral reefs are critical providers of food, economic opportunity, and cultural value in the Pacific Islands. Coral bleaching events, driven by extreme water temperatures, jeopardize reefs’ ability to continue providing these services. Climate change is increasing the frequency and intensity of marine heat waves leading to bleaching events, reducing the amount of time for full recovery...

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...

Stream fish are in peril from a changing climate, particularly for species with restricted distributions or populations on the southern edge of their range. For these fish, the opportunity to escape warming temperatures is limited by the network of stream channels accessible to them. To deal with temperatures beyond their physical capacity, fishes must move, adapt, or die. However...