I am a PhD candidate at the Atmospheric Chemistry Modeling Group, Harvard University.

Please feel free to reach out to me to talk about all kinds of research at hplin at seas.harvard.edu.

Research Focus

My work is focused on the development and evaluation of meteorology-chemistry and chemistry-climate models. Availability of more powerful compute resources has made on-line atmospheric chemistry modeling accessible. Atmospheric chemists can take advantage of on-line meteorology for forecasting and explore interactions and feedback between meteorology and chemistry. Climate scientists can use on-line chemistry to investigate effects of chemistry on climate and future air quality scenarios.

WRF-GC two-way meteorology-chemistry model

I led the technical development of the WRF-GC model coupling the Weather Research and Forecasting Model (WRF) with the GEOS-Chem atmospheric chemistry model. The WRF-GC model is now maintained at the Atmospheric Chemistry and Climate Group at SUSTech.

CESM2 with the GEOS-Chem chemical module

I assisted in the development of the GEOS-Chem chemical module within the Community Earth System Model (CESM2), providing users with an alternative chemical option to CAM-chem. My major contribution was the development of the Harmonized Emissions Component (HEMCO) Version 3 to provide harmonized emissions between CAM-chem, GEOS-Chem within CESM, WRF-GC, and the GEOS-Chem model.

Kinetic Pre-Processor (KPP) and adaptive chemical solvers

I co-led the development of an adaptive chemical solver for the Kinetic Pre-Processor (KPP) version 3, aiming to speed up the computation of chemistry within models while maintaining acceptable accuracy. I also assisted in developing machine learning-based chemistry solvers within the GEOS-Chem model in collaboration with Makoto Kelp, et al.

High-Performance Computing

I assist in efforts in porting the GEOS-Chem model and other atmospheric chemistry models such as WRF-GC to the cloud, scaling up to thousands of cores and generating terabytes of data per day. I am always excited about writing high-performance, scalable code to do better science.


6 peer reviewed publications, 2 first-authored. H-index: 4. My Google Scholar.

6. Xu, X., Feng, X., Lin, H., Zhang, P., Huang, S., Song, Z., Peng, Y., Fu, T.-M., and Zhang, Y.: Modelling the High Mercury Wet deposition in the Southeastern US by WRF-GC, Geosci. Model Dev., 2022. PDF

5. Lin, H., Jacob, D. J., Lundgren, E. W., Sulprizio, M. P., Keller, C. A., Fritz, T. M., Eastham, S. D., Emmons, L. K., Campbell, P. C., Baker, B., Saylor, R. D., and Montuoro, R.: Harmonized Emissions Component (HEMCO) 3.0 as a versatile emissions component for atmospheric models: application in the GEOS-Chem, NASA GEOS, WRF-GC, CESM2, NOAA GEFS-Aerosol, and NOAA UFS models, Geosci. Model Dev., 2021. PDF

4. Feng, X., Lin, H., Fu, T-M., Sulprizio, M. P., Zhuang, J., Jacob, D. J., Tian, H., Ma, Y., Zhang, L., Wang, X. and Chen, Q.: WRF-GC (v2.0): online two-way coupling of WRF (v3.9.1.1) and GEOS-Chem (v12.7.2) for modeling regional atmospheric chemistry-meteorology interactions, Geosci. Model Dev., 2021. PDF

3. Zhang, R., Zhang, Y., Lin, H., Feng, X., Fu, T-M. and Wang, Y.: NOx emission reduction and recovery during COVID-19 in East China, Atmosphere, 2020. PDF [ESI top 1% highly cited paper as of November/December 2021]

2. Lin, H., Feng, X., Fu, T-M., Tian, H., Ma, Y., Zhang, L., Jacob, D. J., Yantosca, R. M., Sulprizio, M. P., Lundgren, E. W., Zhuang, J., Zhang, Q., Lu, X., Zhang, L., Shen, L., Guo, J., Eastham, S. D. and Keller, C. A.: WRF-GC (v1.0): online coupling of WRF (v3.9.1.1) and GEOS-Chem (v12.2.1) for regional atmospheric chemistry modeling, Part 1: description of the one-way model (v1.0), Geosci. Model Dev., 2020. PDF

1. Zhuang, J., Jacob, D.J., Lin, H., Lundgren, E.W., Yantosca, R.M., Flo Gaya, J., Sulprizio, M.P. and Eastham, S.D., Efficient high-performance computing on the Amazon Web Services cloud with over a thousand cores: application to global atmospheric chemistry simulations at 50-km resolution with GEOS-Chem 12.3.2, J. Adv. Model. Earth Sy., 2020. ePDF

In review

1. Fritz, T. M., Eastham, S. D., Emmons, L. K., Lin, H., Lundgren, E. W., Goldhaber, S., Barrett, S. R. H., and Jacob, D. J.: Implementation and evaluation of the GEOS-Chem chemistry module version 13.1.2 within the Community Earth System Model v2.1, submitted to Geosci. Model Dev., in review, 2022. Preprint at EGUsphere

2. Kelp, M., Jacob, D., Lin, H., and Sulprizio, M. P.: An Online-Learned Neural Network Chemical Solver for Stable Long-Term Global Simulations of Atmospheric Chemistry, submitted to J. Adv. Model. Earth Sy., in review, 2021.

Conference Presentations

  • Development of the Harmonized Emissions Component (HEMCO) as an online emissions component for CAM-chem and CESM-GC, 2021 CESM Atmosphere Model, Whole Atmosphere, & Chemistry Climate Working Group Meeting, February 2021. Meeting link
  • 12.3 - WRF-GC: Online Coupling of WRF and GEOS-Chem for Urban/Regional Atmospheric Chemistry Modeling, Session 12 Joint with the 23rd Conference on Atmospheric Chemistry Regional Air Quality. Part II: Impacts of Energy and Agriculture, 101st American Meteorological Society Annual Meeting, Online, January 2021. View Presentation
  • A022-04 Development of the Harmonized Emissions Component (HEMCO) 3.0 as a general emissions component for atmospheric models, eLightning presentation at AGU Fall Meeting 2020, Online, December 2020. View Poster (requires AGU login)
  • WRF-GC: Running WRF with the GEOS-Chem chemical module: Model Clinic, 9th International GEOS-Chem Meeting (IGC9), at Harvard University, Cambridge, MA, USA, May 2019. WRF-GC Website
  • Development of a Meteorology-Chemistry Coupled Model: WRF-GC, Preliminary Results (poster), American Geosciences Union/Chinese Academy of Sciences Joint Meeting (AJM JING Meeting), at Xi’an, China, October 2018.
  • Coupling GEOS-Chem with WRF: Developing a new Meteorology-Chemistry Coupled Model, Preliminary Results (poster). 1st GEOS-Chem Asia Meeting (GCA1), at NUIST, Nanjing, China, May 2018.