A high-resolution regional CTDAS-WRF-Chem framework for constraining methane emissions over East Asia

Abstract

As a major methane hotspot, East Asia urgently requires high-resolution, reliable emission maps to support mitigation strategies. We applied and evaluated a regional inversion framework by coupling the CarbonTracker Data Assimilation Shell (CTDAS) with WRF-Chem. This framework was used to perform inversions across East Asia (13.3°N–49.3°N, 99.8°E–150.2°E) for 2022 based on ground-based atmospheric methane observations, using a 9 km nested grid focused on the Yangtze River Delta (YRD) in eastern China. Pseudo-observation tests show robust recovery of the prescribed “true” emissions across three well-constrained regions: the YRD, Korea, and northern Japan (≥37°N). Among eight tested parameters and input datasets, the number of ensemble member accounts for most of the uncertainty reduction. In the YRD sectoral inversion, major sources (fuel exploitation, waste, natural, and agricultural emissions) are effectively corrected, whereas minor contributors (

Authors 4

1. Mengrong Lu

   University of Groningen

   Affiliation as printed

   Integrated Research on Energy, Environment and Society (IREES), Energy and Sustainability Research InstituteGroningen (ESRIG), University of Groningen, Groningen, The Netherlands

2. Huilin Chen corresponding

   University of Groningen · Nanjing University

   Affiliation as printed

   Centre for Isotope Research (CIO), Energy and Sustainability Research InstituteGroningen (ESRIG), University of Groningen, Groningen, The Netherlands

   Joint International Research Laboratoryof Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing, China

3. Sander Houweling corresponding Aachen SRON Netherlands Institute for Space Research

   Space Research Organisation Netherlands · Vrije Universiteit Amsterdam

   Affiliation as printed

   Department of Earth Sciences, Vrije Universiteit Amsterdam, Amsterdam, 1081 HV, Netherlands

   SRON Netherlands Institute for Space Research, Leiden, 2333 CA, Netherlands

4. Klaus Hubacek

   University of Groningen

   Affiliation as printed

   Integrated Research on Energy, Environment and Society (IREES), Energy and Sustainability Research InstituteGroningen (ESRIG), University of Groningen, Groningen, The Netherlands