O&M Building, Room 1104A
Department of Atmospheric Sciences
College Station, Texas 77843
Dr. rer. nat. Chemistry, Johannes Gutenberg University, Mainz, Germany, 1997
Gunnar W. Schade
My main research interests lie in the exchange of trace gases between the biosphere and the atmosphere. Both soils and plants exhange many different trace gases with the atmosphere, and these processes can contribute in different ways to the global biogeochmical cycles of elements such as carbon and nitrogen. Examples are the photosynthetic uptake of carbon dioxide,CO2, into green plants or the simultaneous reactive deposition of ozone, O3, into those plants, damaging their photosynthetic apparatus. These two trace gases are also good examples of one that is central to the global carbon cycle but does not directly influence atmospheric chemistry, and one that is central to atmospheric chemistry but does not play a major role in any biogeochemical cycle. If we want to understand the roles these and other trace gases play in biogeochemical cycling and atmospheric chemistry, we need to study their sources, sinks, and transformations in the atmosphere, and their interplay, both in the laboratory and the field. In nature, both the physical and the biological environment can be a major driver of trace gas exchanges. My research involves the detailed study of these processes under current day conditions, the improvement of existing and the development of improved models that describe the exchange process(es) as accurately as possible, and the study of physical and chemical feedback mechanisms between the biosphere and the atmosphere. An example for the latter is the partial control of the atmosphere's oxidative capacity by biospheric volatile organic compound (BVOC) emissions, such as isoprene.
We study these BVOC emissions and other exchanges under both laboratory and field conditions. My previous field-based studies included a tower platform in California and a conventionally managed agricultural field plot in Germany. We are using both 'classic' enclosure techniques and several micrometeorological techniques to measure trace gas exchanges between soils, plants, and the atmosphere. For trace gas analysis, we use established infrared or UV absorption analyzers, both gas chromatographic and mass spectrometric techniques, but also specialized systems to target a specific trace gas, such as our past methanol/formaldehyde instrument.
Our main project until 2013 was the measurement of energy and trace gas fluxes in an urban area (click the link to that project on the right-hand side of the screen), in which we focused on both anthropogenic and biogenic fluxes. We ran an extensive flux site in Houston from summer 2007 to spring 2013, and are still busy with data analysis and preparing theses/manuscripts. Graduate student Chang Hyoun Park's PhD thesis revolved around our VOC flux measurements using a new portable REA-GC-dual-FID system. EPA funded us in 2010 to commence research at this site. Graduate student Nick Werner carried out a NOAA funded study to analyze the CO2 data from the tower and distinguish between anthropogenic and biogenic contributions to the net fluxes. Graduate student Marty Hale continued ChangHyoun Park's work analyzing the measured VOC fluxes, testing a footprint model and providing a more long-term perspective on emissions.
We were also funded a new investigator award by NSF in 2010. In that project we measure leaf physiology and BVOC emissions from oak tree species in the Houston area (see links on the right). Our hypothesis revolves around using the urban climate as a proxy for climate change effects on photosynthsis and isoprene emissions, based on the findings that urban areas - on average - are warmer, exert more water stress on plants, and have higher CO2 concentrations than the surrounding countryside. Graduate student Jonathan Gramann analyzed meteorological and plant physiological data from our field sites and postdoctoral researcher Dr. Csengele Barta carried out detailed physiological and isoprene measurements and analyses that will enter our first manuscript comparing 2011 drought data with 2012 data in 2014.
- Sri Harsha Kota, Changhyoun Park, Martin C. Hale, Nicholas D. Werner, Gunnar W. Schade, Qi Ying,Estimation of VOC emission factors from flux measurements using a receptor model and footprint analysis, Atmospheric Environment, 82, January 2014, 24-35
- Nicole C. Bouvier-Brown, Gunnar W. Schade, Laurent Misson, Anita Lee, Megan McKay, Allen H. Goldstein, Contributions of biogenic volatile organic compounds to net ecosystem carbon flux in a ponderosa pine plantation, Atmospheric Environment, 60, December 2012, 527-533
- C. Park, G.W. Schade, I. Boedeker, Characteristics of the flux of isoprene and its oxidation products in an urban area, Journal of Geophysical Research, 117(D1), DOI: 10.1029/2011JD015856, 2011
C. Park, G.W. Schade, I. Boedeker, Flux Measurements of Volatile Organic Compounds by the Relaxed Eddy Accumulation method combined with a GC-FID system north of downtown Houston, Texas, Atmospheric Environment, 44, 2605-2614, 2010
N.M., Ngwabie, G.W. Schade, T.G. Custer, S. Linke, and T. Hinz, Abundances and flux estimates of VOCs from a dairy cowshed in Germany, Journal of Environmental Quality, 37, 565-573, 2008
- T. G. Custer and G.W. Schade, Methanol and Acetaldehyde Fluxes Over Ryegrass, Tellus B, 59, 673-684, 2007.
- A. Lee, G.W. Schade, R. Holzinger, and A. H. Goldstein, A comparison of new measurements of total monoterpene flux with improved measurements of speciated monoterpene flux, Atmos. Chem. Phys. 5, 505-513, 2005.
- G. W. Schade and T. G. Custer, OVOC emissions from agricultural soil in northern Germany during the 2003 European heat wave, Atmos. Environ., 38(36), 6105-6114, 2004.
- A. H. Goldstein, M. McKay, M. R. Kurpius, G.W. Schade, A. Lee, R. Holzinger, and R. A. Rasmussen, Forest thinning experiment confirms ozone deposition to forest canopy is dominated by reaction with biogenic VOCs,Geophys. Res. Lett. 31, L22106, doi:10.1029/2004GL021259, 2004.
- Schade, G.W., and Goldstein, A. H., Increase of monoterpene emissions from a pine plantation as a result of mechanical disturbances, Geophys. Res. Lett. 30(7), doi:10.1029/2002GL016138, 2003.
- Spaulding, R., Schade, G.W., Goldstein, A. H., and Charles, M. J., Characterization of Secondary Atmospheric Photooxidation Products: Evidence for Biogenic and Anthropogenic Sources, J. Geophys. Res., 108(D8), 4247, doi:10.1029/2002JD002478, 2003.
- Dreyfus, G., Schade, G. W., and Goldstein, A. H., Observational Constraints on the Contribution of Isoprene Oxidation to Ozone Production on the Western Slope of the Sierra Nevada, CA, J. Geophys. Res., 107(D19), 4365, DOI:10.1029/2001JD001490, 2002.
- Schade, G.W., and Goldstein, A. H., Fluxes of oxygenated volatile organic compounds from a ponderosa pine plantation, J. Geophys. Res., 106(D3), 3111-3124, 2001.
The consensus gap
The Inter-Governmental Panel on Climate Change, specifically its Working Group I that evaluates climate change science, will present its Fifth Assessment Report end September 2013 ( https://www.ipcc-wg1.unibe.ch/, http://www.climatechange2013.org/ ). At that time, a lot of media reporting will flood the airwaves, undoubtedly with much misinterpretation and cherry-picking of the report’s contents. While the report is unlikely going to contain much new information regarding the basics of planetary warming (greenhouse gases and greenhouse effect, ocean acidification, sea level rise, etc.), it is likely to convey a message of increasing risk under the current global business-as-usual increased fossil fuel use scenarios. It is therefore also to be expected that contrarian voices outside the field of science, particularly in the US, will continue their attacks on science and scientists – possibly with increased vigor. Social science research has shown (Fig. 1) that the public as a whole still perceives that there is little scientific consensus on human-caused global warming. The origins of this misperception probably lie in both (i) concerted media campaigns by US contrarian voices that began in the early 1990s, and which have led to widespread misinformation (“information deficit model”), fabrication of “doubt”, and associated discreditation of climate science and scientists, and (ii) the general public’s filtering of climate science information through cultural, faith-based, and political opinion lenses (“cultural cognition model”), leading to rejection of information for unrelated reasons.
Figure 1: The “Consensus Gap” (http://www.skepticalscience.com/, John Cook, University of Queensland, Australia
While it cannot be our task as scientists to convince the unconvinced, or run a media campaign to reach a large number of the citizenry, we should feel obliged as scholars and are often mandated by federal law to reach out and communicate important findings to a broader public. As there are clear indications that
1. the public is misinformed about climate change and associated societal risks, and
2. the publication of IPCC’s 2013 WG I and 2014 WG II reports will create an educational opportunity,
we ought to explore a more proactive approach of public outreach during this school year.
Democracy requires an informed citizenry
We cannot presume any more that our scientific findings get translated into technical or societal progress by publication in scientific journals and popularization by a responsible and fact-based media landscape. While the latter is largely functional in Europe, the entertainment- and headline-focused, politicized, and largely polarized US media environment requires a much more active involvement of scientists to convey scientific knowledge accurately. Assessments have shown (e.g. here, here, or most recently here) that a better informed public on climate change is more likely to support measures to reduce greenhouse gas emissions, and rapid greenhouse gas emission reductions are needed to mitigate warming in the 21st century as climate science shows. What is causing this warming, how it will develop, what consequences this future development may have, and why this brings about a variety of societal risks, is conveyed by us in numerous classes at Texas A&M almost daily. As scholars, we rely for our teaching not only on the newest research, including our own, but also on the IPCC’s assessment reports. It seems fitting therefore, that we cease the opportunity of the publication of the newest reports this fall and spring semesters to reach out to the campus community and the public at large as a way to educate the current and future generation about what awaits us and how that matters.
While stepping out of the ivory tower is not for everyone, I advocate for a more proactive approach of scientists in informing the public about climate change; here, I propose to begin active outreach in the form of short presentations followed by question and answer sessions in public forums designed to provide first-hand information instead of media-based messaging.