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A list of all the posts and pages found on the site. For you robots out there is an XML version available for digesting as well.
Pages
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Posts
Future Blog Post
Published:
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Blog Post number 4
Published:
This is a sample blog post. Lorem ipsum I can’t remember the rest of lorem ipsum and don’t have an internet connection right now. Testing testing testing this blog post. Blog posts are cool.
Blog Post number 3
Published:
This is a sample blog post. Lorem ipsum I can’t remember the rest of lorem ipsum and don’t have an internet connection right now. Testing testing testing this blog post. Blog posts are cool.
Blog Post number 2
Published:
This is a sample blog post. Lorem ipsum I can’t remember the rest of lorem ipsum and don’t have an internet connection right now. Testing testing testing this blog post. Blog posts are cool.
Blog Post number 1
Published:
This is a sample blog post. Lorem ipsum I can’t remember the rest of lorem ipsum and don’t have an internet connection right now. Testing testing testing this blog post. Blog posts are cool.
code_and_data
TROPOMI Methane Inversion
Published:
Code
Code updates of GEOS-Chem Adjoint v35 for TROPOMI methane 4D-Var inversion. Retrieved from the Data Repository for the University of Minnesota, https://doi.org/10.13020/g5xc-nj81, 2021. Available at: https://conservancy.umn.edu/handle/11299/222249.
opportunity
PhD and Postdoctoral Positions in Atmospheric Chemistry, SUNY Albany
Published:
Fall or Spring 2025
portfolio
Carbon-Climate
We study the coupled interactions across biogenic/anthropogenic emissions, atmospheric chemistry, and the broader climate. One example work is diagnosing the temperature dependence of methane emissions, and evaluating the sensitivity of the global methane budget to atmospheric oxidation.
Greenhouse Gas Emissions
Methane is a crucial greenhouse gas whose emission reduction can effectively mitigate climate change on a decadal time scale. Our study explores methane emission characteristics from point sources to global scale. Example findings are as follows.
Point Sources: Methane emission estimates from major livestock and waste operations in the agricultural US Midwest are biased by 40%–80%, revealing large inherent uncertainties in extrapolating limited in-situ data to larger scales.
Regional: We quantified the importance of the US Upper Midwest for the national methane budget. The region includes extensive wetlands and is a world center for livestock operations. Our research reveals substantial carbon mitigation opportunities for the area, that up to 4.5 Tg/y emission reductions could be achieved through widespread deployment of anaerobic digestion.
Global: Interpreting two years of space-based methane measurements from TROPOMI, we showed that two key regions contributing to the accelerating methane growth are the Middle East (with rapid emission increases from fossil fuel explorations) and South Asia (with strong seasonal emissions linked to Monsoon rainfall).
Inverse Modeling
As the volume of new observations explodes, advancing the state of inverse methodology is crucial for full exploitation of these data. Our work evaluates the impact of model transport error for the accuracy of methane source inversions and develop new inversion formalisms for improved identifications of missing greenhouse gas sources from space.
publications
2016
(1) [Translation] The Atmosphere: An Introduction to Meteorology. By F. K. Lutgens and E. J. Tarbuck (2013). Translation into Chinese by X. Chen, Y. Huang, S. Chen, H. Hui, N. Wang, X. Yu, and Y. Meng (2016). Published by Pearson Education Asia Limited and Publishing House of Electronics Industry.
2019
(2) [Dataset] Millet, D. B., Conley, S. A., Gvakharia, A., Kort, E. A., Plant, G., Smith, M. L., and Yu, X.: Airborne measurements from the GEM study. Retrieved from the Data Repository for the University of Minnesota, https://doi.org/10.13020/f50r-zh70, 2019. (available here)
2020
(3) Yu, X., Millet, D. B., Wells, K. C., Griffis, T. J., Chen, X., Baker, J. M., Conley, S. A., Smith, M. L., Gvakharia, A., Kort, E. A., Plant, G., and Wood, J. D.: Top-down constraints on methane point source emissions from animal agriculture and waste based on new airborne measurements in the U.S. Upper Midwest, Journal of Geophysical Research: Biogeosciences, 125, e2019JG005429, 10.1029/2019jg005429, 2020. (available here)
2021
(9) Yu, X., Millet, D. B., and Henze, D. K.: How well can inverse analyses of high-resolution satellite data resolve heterogeneous methane fluxes? Observing system simulation experiments with the GEOS-Chem adjoint model (v35), Geoscientific Model Development, 14(12), 7775–7793, 10.5194/gmd-14-7775-2021, 2021. (available here)
(8) Yu, X., Millet, D. B., Wells, K. C., Henze, D. K., Cao, H., Griffis, T. J., Kort, E. A., Plant, G., Deventer, M. J., Kolka, R. K., Roman, D. T., Davis, K. J., Desai, A. R., Baier, B. C., McKain, K., Czarnetzki, A. C., and Bloom, A. A.: Aircraft-based inversions quantify the importance of wetlands and livestock for Upper Midwest methane emissions, Atmospheric Chemistry and Physics, 21, 951–971, 10.5194/acp-21-951-2021, 2021. (available here)
(7) Gonzalez, A., Millet, D. B., Yu, X., Wells, K. C., Griffis, T. J., Baier, B. C., Campbell, P. C., Choi, Y., DiGangi, J. P., Gvakharia, A., Halliday, H., Kort, E. A., McKain, K., Nowak, J., and Plant, G.: Fossil vs. non-fossil CO sources in the US: New airborne constraints from ACT-America and GEM, Geophysical Research Letters, 48, e2021GL093361, 10.1029/2021GL093361, 2021. (available here)
(6) Hu, C., Griffis, T., Frie, A., Baker, J., Wood, J., Millet, D., Yu, Z., Yu, X., and Czarnetzki, A.: A multi-year constraint on ammonia emissions and deposition within the U.S. Corn Belt. Geophysical Research Letters, 48, e2020GL090865, 10.1029/2020GL090865, 2021. (available here)
(5) [Code] Yu, X., Millet, D. B., and Henze, D. K.: Code updates of GEOS-Chem Adjoint v35 for TROPOMI methane 4D-Var inversion. Retrieved from the Data Repository for the University of Minnesota, https://doi.org/10.13020/g5xc-nj81, 2021. (available here)
(4) [Model archive] Millet, D. B., Gonzalez, A., and Yu, X.: Gonzalez 2021 tagged CO model archive. Retrieved from the Data Repository for the University of Minnesota, https://doi.org/10.13020/p2ze-1y93, 2021. (available here)
2022
(11) Yu, X.: Characterizing methane emissions from point sources to the global budget. Ph.D. Dissertation, University of Minnesota Twin Cities, 2022.
(10) Chen, Z., Jacob, D., Nesser, H., Sulprizio, M., Lorente, A., Varon, D., Lu, X., Shen, L., Qu, Z., Penn E., and Yu, X.: Methane emissions from China: a high-resolution inversion of TROPOMI satellite observations, Atmospheric Chemistry and Physics, 22(16), 10809–10826, 10.5194/acp-22-10809-2022, 2022. (available here)
2023
(13) Yu, X., Millet, D. B., Henze, D. K., Turner, A. J., Delgado, A. L., Bloom, A. A., and Sheng, J.: A high-resolution satellite-based map of global methane emissions reveals missing wetland, fossil fuel, and monsoon sources. Atmospheric Chemistry and Physics, 23, 3325–3346, 10.5194/acp-23-3325-2023, 2023. (available here)
(12) Hu, C., Xiao, W., Griffis, T., Xiao, Q., Wang, S., Zhang, Y., Wang, W., Zhu, L., Chen, X., Yu, X., and Lee, X.: Estimation of anthropogenic CH4 and CO2 emissions in Taiyuan-Jinzhong region: One of the world’s largest emission hotspots. Journal of Geophysical Research: Atmospheres, 128, e2022JD037915, 10.1029/2022JD037915, 2023. (available here)
2024
(16) Jackson, RB, Saunois, M., Martinez, A., Canadell, JG, Yu, X., Li, M., Poulter B., Raymond, PA., Regnier P., Ciais, P., Davis, SJ., and Patra, PK.: Human activities now fuel two-thirds of global methane emissions. Environmental Research Letters, 19(10), 101002, 10.1088/1748-9326/ad6463, 2024. (available here)
(15) Wang, Y., Zhang, C., Pennington, E. A., He, L., Yang, J., Yu, X., Liu, Y., Seinfeld, J. H.: Short-lived air pollutants and climate forcers through the lens of the COVID-19 pandemic. Reviews of Geophysics, 62, e2022RG000773, 10.1029/2022RG000773, 2024. (available here)
(14) Cen, X., He, N., Li, M., Xu, L., Yu, X., Cai, W., Li, X., and Butterbach-Bahl, K.: Suppression of nitrogen deposition on global forest soil CH4 uptake depends on nitrogen status. Global Biogeochemical Cycles, 38, e2024GB008098, 10.1029/2024GB008098, 2024. (available here)
research
Carbon-Climate
We study the coupled interactions across biogenic/anthropogenic emissions, atmospheric chemistry, and the broader climate. Example works are diagnosing the temperature and hydrological dependence of methane emissions, and evaluating the sensitivity of the global methane budget to atmospheric oxidation.
Greenhouse Gas Emissions
Methane is a crucial greenhouse gas whose emission reduction can effectively mitigate climate change on a decadal time scale. Our study explores methane emission characteristics from point sources to global scale.
Point Sources: Methane emission estimates from major livestock and waste operations in the agricultural US Midwest are biased by 40%–80%, revealing large inherent uncertainties in extrapolating limited in-situ data to larger scales. Example findings are here.
Regional: We quantified the importance of the US Upper Midwest for the national methane budget. The region includes extensive wetlands and is a world center for livestock operations. Our research reveals substantial carbon mitigation opportunities for the area, that up to 4.5 Tg/y emission reductions could be achieved through widespread deployment of anaerobic digestion. Example findings are here.
Global: Interpreting two years of space-based methane measurements from TROPOMI, we showed that two key regions contributing to the accelerating methane growth are the Middle East (with rapid emission increases from fossil fuel explorations) and South Asia (with strong seasonal emissions linked to Monsoon rainfall). Example findings are here.
Inverse Modeling
As the volume of new observations explodes, advancing the state of inverse methodology is crucial for full exploitation of these data. Our work evaluates the impact of model transport error for the accuracy of methane source inversions and develop new inversion formalisms for improved identifications of missing greenhouse gas sources from space.
talks
teaching
Teaching experience 1
Undergraduate course, University 1, Department, 2014
This is a description of a teaching experience. You can use markdown like any other post.
Teaching experience 2
Workshop, University 1, Department, 2015
This is a description of a teaching experience. You can use markdown like any other post.