NPS Photo
Changes in Salinity
One major change that has occurred over the last few decades is the amount of salt present in ocean water. In some higher latitude areas in the Northern and Southern Hemispheres, the amount of salt in the water is decreasing, a shift that may be caused by increased rainfall, run-off, and ice melt. In other areas of the world, including large portions of the Atlantic Ocean, the waters are becoming saltier, as a result of increased evaporation, a process that removes water, but leaves salt behind.Though scientists are unsure what the exact causes of these increases and decreases in salt content may be, they are confident that ocean salinity is changing, and will continue to change. As it does, we will see the effects in coastal parks as changes in salinity affect other ocean systems like circulation, currents, and the water cycle. To read more about ocean circulation and climate change in parks, follow the link below about Glacier Bay National Park and Preserve.
Changes in Weather Patterns
Weather patterns are expected to change in a number of ways as a result of human-induced climate change. Severe weather events (such as storms, droughts, heat waves, floods, and more) are expected to become more common and more extreme. The frequency of intense hurricanes may increase. Some regions will receive more rainfall, while others will experience less, leading to floods and droughts. This severe weather may have devastating impacts for many coastal national parks, whose cultural and natural resources are on the front line of destructive events like floods and storms.Scientists also are studying the connection between our warming climate and El Niño – La Niña, the three to five year pattern in the Pacific Ocean of changes in ocean temperature. These changes influence other factors like storms, upwelling, wind and water currents, and precipitation. An El Niño is a time of unusually warm water temperatures in the Pacific Ocean, while a La Niña is characterized by unusually cool temperatures. For eastern Pacific Ocean national parks in Hawaii, California, Oregon, Washington, Alaska, El Niño events are problematic not only for changes bring to ocean environments, but also for their associated extreme weather events and storms. El Niño events can disrupt coastal communities and threaten the breeding and nesting grounds of coastal species such as seals, sea lions, and shorebirds. Climate change may be causing extreme weather events associated with El Niño to become even more extreme, as well as increasing the frequency of El Niño events themselves.
For Further Reading
Hurricane Sandy in National Park SitesU.S. Global Change Research Program
Learn More
Showing results 1-10 of 198
- Type: Article
- Locations: Arches National Park, Aztec Ruins National Monument, Bandelier National Monument, Bent's Old Fort National Historic Site, Big Bend National Park, more »
- Offices: Chihuahuan Desert Inventory & Monitoring Network, Climate Change, Climate Change Response Program, Inventory and Monitoring Division, Mediterranean Coast Inventory & Monitoring Network, more »
When the climate changes enough, the vegetation communities growing in any given place will also change. Under an expanded bimodal climate zone, some plant communities in western national parks are more likely to change than others. National Park Service ecologists and partners investigated the future conditions that may force some of this change. Having this information can help park managers decide whether to resist, direct, or accept the change.
- Type: Article
- Locations: Antietam National Battlefield, Catoctin Mountain Park, George Washington Memorial Parkway, Harpers Ferry National Historical Park, Manassas National Battlefield Park, more »
Freshwater salinization is a growing threat to aquatic life in streams of the National Capital Region. Learn more about the factors influencing salinization and the actions parks can take to help reduce salt pollution.
- Cuyahoga Valley National Park
Climate Impacts in Cuyahoga Valley
- Type: Article
- Locations: Cuyahoga Valley National Park
Northeast Ohio gets seven more inches of annual precipitation than it did in 1960, according to the US Army Corps of Engineers. This often falls as rain during storms that have become more frequent and more intense. Temperatures are warming too. Climate change affects all aspects of life in the valley, across America, and globally. Learn more about how Cuyahoga Valley and other national parks are responding with a Resist-Accept-Direct (RAD) approach.
- Type: Article
- Locations: Tuzigoot National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Climate is the primary driver of ecological processes on Earth. Sonoran Desert Network scientists monitor climate and how it may be changing at Tuzigoot National Monument to better assess the condition of park resources. A weather station in the park has been in operation since 1991. This report summarizes Water Year 2024 climate data.
- Type: Article
- Locations: Tumacácori National Historical Park
- Offices: Sonoran Desert Inventory & Monitoring Network
At Tumacácori National Historical Park, Sonoran Desert Network scientists take measurements of key resources including climate and groundwater. We analyze temperature, precipitation, drought indices, and groundwater levels to better understand how they may be changing over time and to provide context for changes in other natural resources at the park. This report summarizes Water Year 2024 climate and groundwater data.
- Type: Article
- Locations: Tonto National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Climate and water shape ecosystems and how they function. At Tonto National Monument, Sonoran Desert Network scientists monitor key resources, including climate. Understanding how climate may be changing over time is an important part of assessing the condition of other park resources This report summarizes Water Year 2024 climate data from a National Oceanic and Atmospheric Administration weather station in the park.
- Type: Article
- Locations: Saguaro National Park
- Offices: Sonoran Desert Inventory & Monitoring Network
Climate and water shape ecosystems and the services they provide, particularly in arid places like the Sonoran Desert. Sonoran Desert Network scientists monitor climate and groundwater at the park each year. Understanding how these resources may change over time can help explain changes in other resources on the park. This report summarizes the results of climate and groundwater monitoring in Water Year 2024.
- Type: Article
- Locations: Organ Pipe Cactus National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Sonoran Desert Network scientists visit Organ Pipe National Monument every year to monitor climate and groundwater. By taking measurements of these key resources each year, we can better understand how they may be changing over time. This information can help us understand changes in other natural resources on the park as well. This report summarizes Water Year 2024 climate and groundwater data at the park.
- Type: Article
- Locations: Casa Grande Ruins National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Together, climate and hydrology shape ecosystems and the services they provide. Sonoran Desert Network scientists monitor climate and groundwater at Casa Grande Ruins National Monument. Long-term monitoring provides early warning of potential problems, allowing managers to mitigate them before they become worse. This report summarizes climate and groundwater data from Water Year 2024.
- Type: Article
- Locations: Chiricahua National Monument
- Offices: Sonoran Desert Inventory & Monitoring Network
Climate and water are major drivers of ecosystem structure and function. Sonoran Desert Network scientists monitor climate and groundwater at Chiricahua National Monument at one weather station and three wells in the park. Understanding climate and water resources is an important part of assessing the condition of park resources. This report summarizes climate and groundwater data from Water Year 2024.
Last updated: February 25, 2025
