Coastal wetland restoration solve all excess effects of warming---it’s an alt cause.

Coastal wetlands, including salt marshes, mangrove forests, and seagrass meadows, are among the most productive—and threatened—ecosystems on the planet. They provide many benefits to people and nature, such as helping communities adapt to severe storms, flooding, and other climate-related threats and sequestering carbon from the water and atmosphere in their branches, leaves, roots, and underlying soils. These carbon stores are known as “blue carbon” because they are located in places where the land meets the sea. However, these wetland habitats have lost more than a third of their area over the past half-century.

Because coastal wetlands provide carbon sequestration and other important benefits, conservation and restoration of these areas is an important nature-based strategy for mitigating the effects of climate change, and helping communities internationally and across the United States adapt to a changing climate.

Coastal wetlands are among the world’s key ‘carbon sinks’

Coastal wetlands can store far greater amounts of carbon than they naturally release, which makes them one of the world’s most important natural “carbon sinks.” Research suggests that, despite occupying less than 5% of global land area and less than 2% of the ocean, they store roughly 50% of all carbon buried in ocean sediments.1

The capacity of coastal wetlands to capture and store carbon depends on a variety of chemical and physical factors. But a crucial element is the wet, low-oxygen conditions of tidally influenced and submerged soils characteristic of these ecosystems that slow the decay of plant and other organic material. During photosynthesis, plants absorb carbon dioxide from the air and water and use the carbon to support their growth. When the plants die or shed old leaves or roots, the carbon in that decaying organic matter becomes locked in the soils. Healthy coastal wetlands can keep that carbon stored away for millennia, providing a natural way to prevent it from being released into the atmosphere and contributing to climate change.2

However, when coastal ecosystems degrade, those vast stores are released in the form of three major greenhouse gases: carbon dioxide, methane, and nitrous oxide.3 Worldwide, an estimated 450 million metric tons of carbon dioxide—equivalent to more than 97 million cars’ worth—is emitted from the destruction of coastal wetlands each year, accelerating planetary warming and climate change.4

Because protection and restoration of coastal wetlands can substantially contribute to achieving climate mitigation and adaptation goals, these areas have been recognized by the United Nations Framework Convention on Climate Change (UNFCCC).5 To date, coastal wetlands are the only marine ecosystem for which the Intergovernmental Panel on Climate Change, which conducts research in support of the UNFCCC, has developed methodologies for measuring carbon dynamics. But researchers are working to quantify the role that other marine ecosystems such as kelp forests may play in reaching targets by capturing and sequestering carbon.6

Blue Carbon Habitat Fast Facts

Patuxent River

A high school student canoes against a backdrop of salt marsh along the Patuxent River, a tributary of the Chesapeake Bay in the U.S. state of Maryland. Salt marshes are a vital blue carbon ecosystem.

Chesapeake Bay-Maryland National Estuarine Research Reserve

Carbon sequestration is just one benefit of healthy, intact coastal habitats. They also buffer coastlines against damaging waves during severe storms, absorb excess floodwaters, and stabilize shorelines, all of which help communities adapt and become more resilient to climate-related threats. In addition, some blue carbon ecosystems such as seagrass absorb excess carbon dioxide from surrounding waters, reducing the intensity of ocean acidification, a chemical change to seawater that poses a global threat to marine life.7 Coastal ecosystems also provide food and refuge for fish and marine invertebrates that drive global fisheries, and they underpin the cultural heritage and food sovereignty of coastal Indigenous peoples worldwide.8 Here is a brief look at the ecosystem services of the planet’s most abundant types of coastal wetlands.