Satellite record reveals US tidal wetland productivity rose 6% in 20 years
Carbon sequestration, climate regulation, biodiversity support and shoreline protection: These are all benefits provided by tidal wetlands. As the climate changes, the amount of carbon captured by these ...
Carbon sequestration, climate regulation, biodiversity support and shoreline protection: These are all benefits provided by tidal wetlands. As the climate changes, the amount of carbon captured by these vital ecosystems may be changing as well.
Gross primary production (GPP) describes how much carbon is fixed by vegetation via photosynthesis. It's an important metric for understanding potential carbon sequestration, especially as it relates to larger climate mitigation strategies and metrics. Previous studies of tidal wetland carbon dynamics have generally focused on individual locations rather than large-scale trends.
A nationwide view of wetland productivity
Using a satellite data set spanning 2001–2020, Herrmann and team examined how tidal wetland GPP changed across the contiguous United States over the past two decades. The team analyzed regional differences in tidal wetland productivity and examined how climate and vegetation influenced how much carbon was produced over the course of 20 years. The findings are published in the journal Global Biogeochemical Cycles.
The data set used in the study is derived from satellite observations, and it groups wetlands into woody and herbaceous, two types defined by the National Wetlands Inventory. Using a 250-meter (820-foot) resolution and 16-day time stamps of vegetation conditions, combined with information about air temperature and shortwave radiation, researchers modeled the evolution of GPP across seven coastal regions and a countrywide total. In their modeling, the researchers kept the wetland extent fixed at its 2000 distribution.
Climate signals outweigh greenness changes
Overall, GPP increased by 6% over the study period, with the strongest increases occurring in the Gulf and southern Atlantic regions. The increases are driven by climate changes—namely, warming trends and increased sunlight. In contrast, changes in the enhanced vegetation index (EVI), used to quantify greenness, contributed to a slight decrease in overall GPP.
Across all tidal wetland areas, the variation in GPP from year to year is relatively modest, though the most variation occurs in the western Gulf of Mexico, likely thanks to the influence of hurricanes, tropical storms, flooding and drought. Temperature is the strongest driver of variability in tidal wetland productivity, followed by shortwave radiation and then EVI.
Overall, these findings suggest that shifts in temperature and sunlight—rather than changes in vegetation—are responsible for increases in tidal wetland productivity and that this information should be considered when managing tidal wetlands or creating carbon cycle models.
Publication details
Maria Herrmann et al, Climate‐Driven Long‐Term Increase in Tidal Wetland Gross Primary Production in the United States, Global Biogeochemical Cycles (2026). DOI: 10.1029/2026gb009093
Who's behind this story?
MA in English, copy editor since 2021 with experience in higher education and health content. Dedicated to trustworthy science news. Full profile →
Master's in physics with research experience. Long-time science news enthusiast. Plays key role in Science X's editorial success. Full profile →
This story is republished courtesy of Eos, hosted by the American Geophysical Union. Read the original story here.
Citation: Satellite record reveals US tidal wetland productivity rose 6% in 20 years (2026, July 7) retrieved 14 July 2026 from https://phys.org/news/2026-07-satellite-reveals-tidal-wetland-productivity.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.