Description:    This study aims to examine how future climate, temperature and precipitation specifically, are expected to change under the A2, A1B, and B1 emission scenarios over the six states that make up the Southern Climate Impacts Planning Program (SCIPP): Oklahoma, Texas, Arkansas, Louisiana, Tennessee, and Mississippi. SCIPP is a member of the National Oceanic and Atmospheric Administration-funded Regional Integrated Sciences and Assessments network, a program which aims to better connect climate-related scientific research with in-the-field decision-making processes. The results of the study found that the average temperature over the study area is anticipated to increase by 1.7°C to 2.4°C in the twenty-first century based on the different emission scenarios with a rate of change that is more pronounced during the second half of the century. Summer and fall seasons are projected to have more significant temperature increases, while the northwestern portions of the region are projected to experience more significant increases than the Gulf coast region. Precipitation projections, conversely, do not exhibit a discernible upward or downward trend. Late twenty-first century exhibits slightly more precipitation than the early century, based on the A1B and B1 scenario, and fall and winter are projected to become wetter than the late twentieth century as a whole. Climate changes on the city level show that greater warming will happened in inland cities such as Oklahoma City and El Paso, and heavier precipitation in Nashville. These changes have profound implications for local water resources management as well as broader regional decision making. These results represent an initial phase of a broader study that is being undertaken to assist SCIPP regional and local water planning efforts in an effort to more closely link climate modeling to longer-term water resources management and to continue assessing climate change impacts on regional hazards management in the South. Content Type Journal Article Category Original Paper Pages 1-16 DOI 10.1007/s00704-011-0567-9 Authors Lu Liu, School of Civil Engineering and Environmental Science, University of Oklahoma, 120 David L. Boren Blvd., National Weather Center ARRC 4610 Suite, Norman, OK 73072, USA Yang Hong, School of Civil Engineering and Environmental Science, University of Oklahoma, 120 David L. Boren Blvd., National Weather Center ARRC 4610 Suite, Norman, OK 73072, USA James E. Hocker, Southern Climate Impacts Planning Program, Oklahoma Climate Survey, University of Oklahoma, Norman, OK, USA Mark A. Shafer, Southern Climate Impacts Planning Program, Oklahoma Climate Survey, University of Oklahoma, Norman, OK, USA Lynne M. Carter, Southern Climate Impacts Planning Program, Louisiana State University, Baton Rouge, LA, USA Jonathan J. Gourley, NOAA/National Severe Storms Laboratory, Norman, OK 73072, USA Christopher N. Bednarczyk, School of Civil Engineering and Environmental Science, University of Oklahoma, 120 David L. Boren Blvd., National Weather Center ARRC 4610 Suite, Norman, OK 73072, USA Bin Yong, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098 China Pradeep Adhikari, School of Civil Engineering and Environmental Science, University of Oklahoma, 120 David L. Boren Blvd., National Weather Center ARRC 4610 Suite, Norman, OK 73072, USA Journal Theoretical and Applied Climatology Online ISSN 1434-4483 Print ISSN 0177-798X

Description: Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO 3 − ) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L 16 design, comprising 16 experimental units. Within this L 16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N 2 O), methane (CH 4 ) and carbon dioxide (CO 2 ) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO 3 − addition were the main factors affecting N 2 O fluxes, whilst glucose, NO 3 − and soil temperature were the main factors affecting CO 2 and CH 4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time.