GFDL/NOAA
201 Forrestal Rd.
Princeton, NJ 08542-0308
phone: (609) 452-5346
fax: (609) 987-5063
Email: Junfeng.Liu@noaa.gov
or: jliu@princeton.edu
Education
Ph.D., Public Administration, Princeton University, Princeton, NJ, U.S.A.
M.S., Environmental Sciences,
Peking University, Beijing, China
Sc.B.,
Chemistry, Peking University, Beijing, China
Research
My research interests are to understand the chemical-climate interactions as well as the patterns of inter-continental transport of air pollution and the related environmental policies for global air pollution control. Specifically, I'd like to 1) use global climate model, coupled full chemistry, to analyze the physical and chemical evolution of air pollutants, 2) evaluate the impacts of anthropogenic emissions on human health, ecosystems, agriculture and global climate change, 3) explore the policy motivations among industrialized and developing nations to address the air quality problem of local and inter-continental transport of air pollution, and (4) develop effective environmental policies (both local and international) on air pollution control.
My previous research focuses on the source-receptor relationship of inter-continental transport of fine aerosols (including sulfate, black carbon, organic carbon and mineral dust), and evaluates the related human health impact. We conduct a 7-year simulation with the tagged aerosol species originated from 10 continental regions. Both anthropogenic and biomass burning emission inventories are selected for the year 2000. We evaluate the model results with the observations around the world, including IMPROVE (United States - rural), EMEP (Europe), EANET (East Asia), and the global data collected by the University of Miami (RSMAS). The health impact (i.e., premature mortality) caused by domestic and intercontinental sources of fine aerosols are quantified. To address the policy relevant questions related to inter-continental transport of air pollution, we defined an "influence potential", namely the emission normalized, population weighted air pollution concentrations. Based on the modeling results and influence potential ratio among different continents, we investigate the potential incentives among industrialized and developing regions to cooperatively mitigate sulfate emissions.
In addition, my previous research also focuses on determining the pathways and timescales of inter-continental transport of air pollution. In particular, I have used MOZART-2, a 3D global chemical tracer model (Model of Ozone And Related Tracers, version 2) driven with NCEP reanalysis meteorology to examine the trans-Pacific transport patterns for Asian and European emissions. Nine continental tracers (with first order decay rate) were used and their trans-Pacific transport potentials, including seasonal and inter-annual variability, were estimated. Transport pathways and regions with the highest transport ability were identified. Meteorological factors that control the inter-annual variability of trans-Pacific transport were investigated. We created an index, called Eastern Pacific Index (EPI), which can capture most of the inter-annual variations of the trans-Pacific transport. Moreover, I have evaluated the relationship between tracer lifetimes and tracer concentrations, and quantified the average transport time for inter-continental transport. We determined that the average transport time depends on the tracer lifetime used and can be approximately represented by an 'equivalent circulation' approach. In addition, the average time of inter-continental transport that we calculated was approximately 3-weeks, 1-2 weeks longer than has been observed in rapidly transported plumes.
My current research focuses on using global climate model (GFDL-AM3 model) to understand the chemical-climate interactions and the related effects on present and future inter-continental transport of air pollution.
Publications
Liu, J., D.L. Mauzerall, L.W. Horowitz, P. Ginoux, A.M. Fiore. Evaluating Inter-continental transport of fine aerosols: (1) Methodology, global aerosol distribution and optical depth, Atmospheric Environment, accepted, 2009. [full text] [Auxiliary]
Liu, J., D.L. Mauzerall, L.W.
Horowitz. Evaluating Inter-continental transport of fine aerosols: (2) Global
Health Impacts, submitted to Atmospheric Environment 2008.
[full
text] [Auxiliary]
Saikawa, E., V. Naik, L.W. Horowitz, J. Liu, D.L. Mauzerall, Present and potential future contributions of sulfate, black and organic carbon aerosols from China to global air quality, premature mortality and radiative forcing, Atmospheric Environment, accepted, 2009. [full text]
Liu, J., Mauzerall, D. L., Horowitz, L.W. Source-Receptor Relationships between East Asian Sulfur Dioxide Emissions and Northern Hemisphere Sulfate Concentrations, Atmos. Chem. Phys., 8, 3721-3733, 2008 [full text]
Liu, J. and D. L. Mauzerall, Evaluating the potential influence of inter-continental transport of sulfate aerosols on air quality, Environ. Res. Lett. 2 045029, doi:10.1088/1748-9326/2/4/045029, 2007. [full text (pdf)]
Liu, J., “Evaluating Inter-Continental Transport of Air Pollution and Its Impacts on Global Health: Implications for Regional and Global Cooperation to Mitigate Long-Range Trans-Boundary Transport of Air Pollution”, Ph.D. Dissertation, 2006
Liu, J., and Mauzerall, D. L., “Estimating the Average Time for Inter-continental Transport of Air Pollutants,” Geophysical Research Letters, 32, L11814, doi:10.1029/ 2005GL022619, 2005.
Liu, J., Mauzerall, D. L., Horowitz, L.W., "Analysis of Seasonal and Inter-annual Variability in Transpacific Transport,” Journal of Geophysical Research-Atmosphere, 110, D04302, doi:10.1029/2004JD005207, 2005. Downloading the EPI index for 1991-2001
Liu, J., “Environmental Taxation Policy on Recovery of Ecosystems in Western China”, China Environment News, Dec 7, 2004 (in Chinese)
Mackie, D., J. Liu, Y.S. Loh, and V. Thomas, “No Evidence of Dioxin Cancer Threshold”, Environmental Health Perspectives, 111 (9), 1145-1147, 2003.
Liu J., Li J., “A comparison of Atmospheric Photo-Chemical Mechanisms（I）O3 and NOx”. Environmental Chemistry, Vol.20, No.4, 2001 (in Chinese)
Liu J., Li J., “A comparison of Atmospheric Photo-Chemical Mechanisms （II）HOx and Photo-Chemical Products”. Environmental Chemistry, Vol.20, No.4, 2001 (in Chinese)
Liu J., “A Comparison of Four Photochemical Reaction Mechanisms”, Master Thesis, Peking University, 2000 (in Chinese)
Liu J., Li J., Bai Y.. “The Parameterization of Hydrogen Ion Concentration in the Rainfall”. Research of Environmental Sciences, 13(1), 18-21, 2000 (in Chinese)
Liu J., Li J., Bai Y.. “The Numerical Solvers for Atmospheric Chemistry Models”. Research of Environmental Sciences, 13(1), 39-44, 2000 (in Chinese)
Liu J., “The Synthesis and Characterization of Electric Poly-Aniline”, Undergraduate Thesis, Peking University, 1997 (in Chinese)