Satellite quantification of methane emissions and oil–gas methane intensities from individual countries in the Middle East and North Africa: implications for climate action

Abstract

Abstract. We use 2019 TROPOMI satellite observations of atmospheric methane in an analytical inversion to quantify methane emissions from the Middle East and North Africa at up to ∼25 km × 25 km resolution, using spatially allocated national United Nations Framework Convention on Climate Change (UNFCCC) reports as prior estimates for the fuel sector. Our resulting best estimate of anthropogenic emissions for the region is 35 % higher than the prior bottom-up inventories (+103 % for gas, +53 % for waste, +49 % for livestock, −14 % for oil) with large variability across countries. Oil and gas account for 38 % of total anthropogenic emissions in the region. TROPOMI observations can effectively optimize and separate national emissions by sector for most of the 23 countries in the region, with 6 countries accounting for most of total anthropogenic emissions including Iran (5.3 (5.0–5.5) Tg a−1; best estimate and uncertainty range), Turkmenistan (4.4 (2.8–5.1) Tg a−1), Saudi Arabia (4.3 (2.4–6.0) Tg a−1), Algeria (3.5 (2.4–4.4) Tg a−1), Egypt (3.4 (2.5–4.0) Tg a−1), and Turkey (3.0 (2.0–4.1) Tg a−1). Most oil–gas emissions are from the production (upstream) subsector, but Iran, Turkmenistan, and Saudi Arabia have large gas emissions from transmission and distribution subsectors. We identify a high number of annual oil–gas emission hotspots in Turkmenistan, Algeria, and Oman and offshore in the Persian Gulf. We show that oil–gas methane emissions for individual countries are not related to production, invalidating a basic premise in the construction of activity-based bottom-up inventories. Instead, local infrastructure and management practices appear to be key drivers of oil–gas emissions, emphasizing the need for including top-down information from atmospheric observations in the construction of oil–gas emission inventories. We examined the methane intensity, defined as the upstream oil–gas emission per unit of methane gas produced, as a measure of the potential for decreasing emissions from the oil–gas sector and using as reference the 0.2 % target set by the industry. We find that the methane intensity in most countries is considerably higher than this target, reflecting leaky infrastructure combined with deliberate venting or incomplete flaring of gas. However, we also find that Kuwait, Saudi Arabia, and Qatar meet the industry target and thus show that the target is achievable through the capture of associated gas, modern infrastructure, and the concentration of operations. Decreasing methane intensities across the Middle East and North Africa to 0.2 % would achieve a 90 % decrease in oil–gas upstream emissions and a 26 % decrease in total anthropogenic methane emissions in the region, making a significant contribution toward the Global Methane Pledge.

Assessing the Relative Importance of Satellite-Detected Methane Superemitters in Quantifying Total Emissions for Oil and Gas Production Areas in Algeria

“…Previous satellite-based transport model inversions have estimated Algerian methane emissions at 1.82 [1.68−1.96] Tg/yr for 2017 57 and at 3.7 ± 0.3 Tg/yr for 2019, 58 based on GOSAT, and at 3.5 [2.4−4.4] Tg/yr for 2019, based on TROPOMI. 59 Attribution of these national total emissions to different source sectors differs significantly: Western et al 57 attribute 80% of total Algerian emissions to O/G activity in the prior, but do not revise this percentage based on the inversion; Worden et al 58 estimate O/G emissions at 3.2 Tg/yr; and Chen et al 59 estimate lower O/G emissions at 2.09 Tg/yr and separately estimate O/G upstream and midstream emissions at 1.60 and 0.29 Tg/year, respectively. In general, these emission estimates are somewhat higher than what we report here, but as indicated above, our national upscaling based on only two fields introduces additional uncertainty.…”

Current potential of CH4 emission estimates using TROPOMI in the Middle East

“…Lauvaux et al (2022) found fewer detections of ultra-emitters (>25 kg/hour) in Middle Eastern countries like Iraq, Saudi Arabia than other hot-spot regions like the U.S. from TROPOMI observations. Chen et al, (2023) also revealed large discrepancies between a priori and posterior emission inventory derived from satellites over the Middle East.…”

Interpreting the Seasonality of Atmospheric Methane

“…Surface observations are from the remote sites of the NOAA network (Schuldt et al., 2023) and satellite observations are from a blended TROPOMI + GOSAT dry air column mole fraction (XCH 4 ) retrieval that combines the observational density of TROPOMI with the precision of GOSAT (Balasus et al., 2023). GEOS‐Chem is widely used as forward model in global and regional inverse analyses (e.g., Chen et al., 2023; Feng et al., 2023; Worden et al., 2022; Zhang et al., 2022). We show that GEOS‐Chem driven by its default prior budget terms has a large seasonal low bias in the Northern Hemisphere.…”