Future methane emissions from lakes and reservoirs.

Area of Science:

• Environmental Science
• Climate Science
• Geochemistry

Background:

• Global lakes and reservoirs emit approximately 10% of global methane (CH4).
• Understanding the sensitivity of these emissions to climate change is crucial.
• Future projections of CH4 fluxes are needed to inform mitigation strategies.

Purpose of the Study:

• To model and predict future open-water methane (CH4) fluxes from lakes and reservoirs globally.
• To assess the impact of different climate change scenarios (IPCC SSPs) on CH4 emissions.
• To identify key drivers influencing future CH4 emissions from inland waters.

Main Methods:

• Utilized data-driven, globally gridded modeling approaches.
• Incorporated multiple predictor variables and peer-reviewed, in situ-verified flux data.
• Simulated CH4 fluxes under various IPCC Shared Socioeconomic Pathways (SSPs).

Main Results:

• Projected increases in total lake and reservoir CH4 emissions ranging from 24% to 91% by 2080-2099.
• Temperature and seasonality changes were identified as dominant factors driving emission increases.
• Changes in water body area and nutrient loads also significantly contributed to reservoir emissions.

Conclusions:

• Minimizing climate change is urgent to prevent substantial increases in future inland water CH4 emissions.
• Significant CH4 emission changes are predicted across all latitudes.
• The study underscores the critical role of inland waters in the global methane cycle under future climate conditions.