I am a trace gas biogeochemist who tracks environmentally important chemicals: their mechanisms of production and consumption, their rates of exchange between land and atmosphere, and their impacts on atmospheric composition. Most of these gases are known as Biogenic Volatile Organic Compounds (BVOCs), owing to their biological origin. BVOCs have a complex mosaic of sources that are important to understand because these gases are relevant for climate regulation, aerosol formation, stratospheric ozone depletion, regional air quality, and plant and microbial biochemistry. Moreover, the emissions and uptake of these compounds are affected by our changing environment, including land use, climate change, sea level rise, spread of invasive species, and direct emissions by human activity. Our research group makes precise measurements and interprets those data to make sense our natural world. Our laboratory combines field sampling and laboratory experiments, and we utilize micrometeorology and analytical chemistry tools to conduct our measurements.
As of 2017, I serve as the Interim Faculty Director for the Sagehen Creek Field Research station at Truckee, CA (one of the UC Natural Reserves managed by UC Berkeley). I am also a Resident Faculty member for Units 1 and 4.
My primary appointment is in the Department of Geography. Since 2012, I have had a joint appointment in ESPM (Ecosystem Sciences). This means that I can accept graduate students through either Geography or ESPM as the primary advisor, and I can also serve on ESPM graduate student committees as either an internal or external member. Please contact me if you are interested in working with me and need advice on how to apply to graduate school.
1992 B.A. Earth & Planetary Sciences (Atmospheres and Oceans) Harvard University
1994 Graduate Diploma. Resource & Env’t Management Australian National University
2001 Ph.D. Earth Sciences (Geochemistry) Scripps Institution of Oceanography, UCSD
Atmospheric science: stratospheric ozone depletion, air quality and greenhouse gases. Trace gas biogeochemistry of halocarbons, hydrocarbons and reduced sulfur compounds. Biosphere-atmosphere flux measurements in natural and human-impacted landscapes. Education development in ocean, climate and atmospheric sciences.
Although trace gases constitute less than 1% of the composition of the atmosphere, they are compounds that regulate the Earth’s greenhouse effect, the balance of stratospheric ozone, and most of the chemical reactions in the atmosphere. In our trace gas biogeochemistry lab, we seek to quantify the biosphere-atmosphere exchange of environmentally important trace gases and to identify the physical and biological controls on those fluxes. We conduct our work in a wide range of natural and human-dominated ecosystems, including Arctic tundra, temperate grasslands, salt-affected lands, arid and semi-arid shrublands, boreal forest, temperate forest, and tropical ecosystems. This work will help to quantify globally significant sources and sinks, to assess the atmospheric lifetimes of these compounds (how long these compounds persist in the atmosphere), and to elucidate key biogeochemical processes that occur in nature. We focus on halogen, sulfur, and carbon containing compounds that catalyze ozone destruction; influence the radiative energy balance of the planet; and/or act as proxies or byproducts of important ecosystem processes. This work is very interdisciplinary, involving the tools of analytical and atmospheric chemistry, soil geochemistry and microbiology, plant biology and genetics, ecosystem ecology and physical geography. Consequently, our laboratory invites the participation of students from a wide variety of backgrounds.
Whelan M.E. and R.C. Rhew, Reduced sulfur trace gas exchange between a seasonally dry grassland and the atmosphere, Biogeochemistry, doi: 10.1007/s10533-016-0207-7 (2016).
Rhew, R.C. and J. Happell, The atmospheric partial lifetime of carbon tetrachloride with respect to the global soil sink, Geophysical Research Letters, 43, doi:10.1002/2016GL067839 (2016).
Wang, J-J., Y. Jiao, R.C. Rhew and A. T. Chow, Haloform formation in coastal wetlands along a salinity gradient at South Carolina, United States, Environmental Chemistry, doi: 10.1071/EN15145 (2016).
Whelan M.E. and R.C. Rhew, Carbonyl sulfide produced by abiotic thermal and photo-degradation of soil organic matter from wheat field substrate, Journal of Geophysical Research Biogeosci., 120, doi: 10.1002/2014JG002661 (2015).
Rhew, R.C., Whelan M.E. and D.-H. Min, Large methyl halide emissions from south Texas salt marshes, Biogeosciences, 11, 6427-6434, doi: 10.5194/bg-11-6427-2014 (2014).
Khan, M.A.H., R.C. Rhew, K. Zhou and M.E. Whelan, Halogen biogeochemistry of invasive perennial pepperweed (Lepidium latifolium) in a peatland pasture, Journal of Geophysical Research Biogeosci. 118, 1–9, doi:10.1002/jgrg.20020 (2013).
Whelan M.E., D.-H. Min and R.C. Rhew, Salt marsh vegetation: a carbonyl sulfide (COS) source to the atmosphere, Atmospheric Environment, 73, p. 131-137, doi: 10.1016/j.atmosenv.2013.02.048 (2013).
2001 Edward Frieman Director’s Prize for Outstanding Graduate Student Research
2001-2003 UCAR/NOAA Climate and Global Change Postdoctoral Fellowship
2012-2013 UC Berkeley Presidential Chair Fellows Program
2013 National Center for Atmospheric Research (NCAR) Advanced Study Program Faculty Fellow
2014 Cooperative Institute for Research in Environmental Sciences (CIRES) Visiting Fellow
2014 Lab Safety Award: Large Field Science Laboratory group
2015 Berkeley Collegium Program Award (Narrowing the Gap Between Teaching and Research)
Natural History of the East Bay Regional Parks §, Freshman seminar (GEOG 24: scheduled 2017)
Introduction to Earth System Science (GEOG 40: 2003, 2004, 2005, 2006, 2008, 2010, 2011)
Introduction to the Oceans* (GEOG/EPS/IB c82: 2008, 2009, 2010)
Top Ten Global Environmental Problems § (GEOG 137: new Fa 2011, 2012, Sp 2015, Sp 2016)
Global Change Biogeochemistry § (GEOG 143: new 2005, 2006, 2009, Sp 2013, Fa2014, Sp 2017).
Communicating Ocean Science* (GEOG c146/EPSc100/IBc100: 2010, 2012, 2016)
Communicating Climate Science* (GEOG 147 (formerly 171): Fa 2014, Fa 2015, Fa 2017).
Introduction to Environmental Sciences* (ESPM15 (formerly ES10): Sp 2012, 2013, Fa 2015, Fa 2016)
GC-Maker Lab 1: Skills and Theory § (GEOG/ESPM c179a: new Fa 2016)
GC-Maker Lab 2: Instrument Development § (GEOG/ESPM c179b: new Sp 2017)
Topics in Biogeochemistry § (GEOG 245: 2004, 2005, 2006, 2007, 2008)
Intro. to Lab & Field Methods in Earth System Science § (GEOG 248: 2004, 2006)
Advances in Environmental Change* (GEOG 243: 2005).
Effective Scientific Communication* (GEOG C302/ESPM C302: new 2007, 2009)