Kenneth Kunkel

Kenneth Kunkel

CICS-NC
NOAA's National Climatic Data Center
Veach-Baley Federal Building
151 Patton Avenue
Asheville, NC 28801-5001
 Telephone: +1 828.257.3137
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Dr. Kunkel’s recent research has focused on climate variability and change, particularly related to extreme events, such as heavy precipitation, heat waves, cold waves, and winter storms. A particular focus has been the historical variations in the frequency and intensity of such extreme events extending from the late 19th Century to the present. An examination of late 19th and early 20th Century variations is important because it establishes the quasi-natural background which provides a context for interpreting recent variations and possible anthropogenic influences.

He has also engaged in the diagnostic analysis of both regional and global climate model output. This has focused on the regional fidelity of model simulations of the climate of the U.S., including such features as the North American monsoon and the lack of 20th Century warming in the central U.S.

He has developed a number of applications of climate data, including a temperature-based model that anticipates the risk of West Nile Virus infections and a soil moisture model for agricultural usage in the Midwest.

As part of his involvement in the National Climate Assessment, he led the development of a nine-part NOAA Technical Report series published in 2013, to support the development of the Third National Climate Assessment report. This series provides regionally-specific information on historical climate trends and scenarios of future climate change.

Dr. Kunkel joined CICS-NC as a Senior Scientist and Science Lead for Assessments, and, the Department of Marine, Earth and Atmospheric Sciences as a Research Professor in September 2010.

2014

Walsh, J., D. Wuebbles, K. Hayhoe, J. Kossin, K. Kunkel, G. Stephens, P. Thorne, R. Vose, M. Wehner, J. Willis, D. Anderson, V. Kharin, T. Knutson, F. Landerer, T. Lenton, J. Kennedy, and R. Somerville, 2014: Appendix 4: Frequently Asked Questions. Climate Change Impacts in the United States: The Third National Climate Assessment, J. M. Melillo, Terese (T.C.) Richmond, and G. W. Yohe, Eds., U.S. Global Change Research Program, 735-789. doi:10.7930/J0KS6PHH.

Walsh, J., D. Wuebbles, K. Hayhoe, J. Kossin, K. Kunkel, G. Stephens, P. Thorne, R. Vose, M. Wehner, J. Willis, D. An­derson, V. Kharin, T. Knutson, F. Landerer, T. Lenton, J. Kennedy, and R. Somerville, 2014: Appendix 3: Climate Science Supplement. Climate Change Impacts in the United States: The Third National Climate Assessment, J. M. Melillo, Terese (T.C.) Richmond, and G. W. Yohe, Eds., U.S. Global Change Research Program, 735-789. doi:10.7930/J0KS6PHH.

Corell, R. W., D. Liverman, K. Dow, K. L. Ebi, K. Kunkel, L. O. Mearns, and J. Melillo, 2014: Ch. 29: Research Needs for Climate and Global Change Assessments. Climate Change Impacts in the United States: The Third National Climate Assessment, J. M. Melillo, Terese (T.C.) Richmond, and G. W. Yohe, Eds., U.S. Global Change Research Program, 707-718. doi:10.7930/J03R0QR3.

Lawrimore, J., T.R. Karl, M. Squires, D.A. Robinson, and K.E. Kunkel, 2014: Trends and variability in severe snowstorms east of the Rocky Mountains. J. Hydromet., accepted.

Wuebbles, D.J., K.E. Kunkel, M. Wehner, and Z. Zobel, 2014: Severe weather in the United States under a changing climate. EOS, 95, 149-150.

Peterson, T.C., T.R. Karl, J.P. Kossin, K.E. Kunkel, J.H. Lawrimore, J.R. McMahon, R.S. Vose and X. Yin, 2014: Changes in weather and climate extremes: State of knowledge relevant to air and water quality in the United States. Journal of the Air & Waste Management Association, 64,184-197, DOI:10.1080/10962247.2013.851044.

Janssen, E., D.J. Wuebbles, K.E. Kunkel, S.C. Olsen, and A. Goodman, 2014: Observed and modeled trends and projections of extreme precipitation over the contiguous United States. Earth’s Future, accepted.

Vose, R.S., S. Applequist, M.A. Bourassa, S.C. Pryor, R.J. Barthelmie, B. Blanton, P.D. Bromirski, H.E. Brooks, A.T. DeGaetano, R.M. Dole, D.R. Easterling, R.E. Jensen, T.R. Karl, R.W. Katz, K. Klink, M.C. Kruk, K.E. Kunkel, M.C. MacCracken, T.C. Peterson, K.Shein, B.R. Thomas, J.E. Walsh, X.L. Wang, M.F. Wehner, D.J. Wuebbles, and R.S. Young, 2014:  Monitoring and understanding changes in Extremes: Extratropical storms, winds, and waves. Bull. Amer. Meteor. Soc., 95, 377-386.

Wuebbles, D.W., G. Meehl, K. Hayhoe, T. R. Karl, K. Kunkel, B. Santer, M. Wehner, B. Colle, E. M. Fischer, R. Fu, A. Goodman, E. Janssen, H. Lee, W. Li, L. N. Long, S. Olsen, A. Seth, J. Sheffield, and L. Sun, 2013:  CMIP5 climate model analyses: Climate extremes in the United States. Bull. Amer. Meteor. Soc., accepted

Kunkel, K.E. and D.R. Easterling, 2014: Extreme precipitation events: Data issues and meteorological causes. U.S. CLIVAR Variations, 12, 1-3.

Kunkel, K.E., 2014: Climate Change Research Strategy for Atmospheric Processes Impacting the Lake Tahoe Basin. Desert Research Institute Technical Report, 35 pp.

2013

Konrad, C.E., C.M. Fuhrmann, A. Bilot, B.D. Keim, M.C. Kruk, K.E. Kunkel, H. Needham, M. Shafer, and L. Stevens (2013), Climate of the Southeast USA: Past, Present, and Future. Climate of the Southeast United States: Variability, Change, Impacts, and Vulnerability. K.T. Ingram, K. Dow, L. Carter, and J. Anderson, Eds., Island Press, Washington, D.C., 8-42.

Cayan, D., M. Tyree, K.E. Kunkel, C. Castro, A. Gershunov, J. Barsugli, A.J. Ray, J. Overpeck, M. Anderson, J. Russell, B. Rajagopalan, I. Rangwala, and P.Duffy, 2013: Future Climate: Projected Average. In Assessment of Climate Change in the Southwest United States: a Report Prepared for the National Climate Assessment, edited by Garfin, G., Jardine, A., Merideth, R., Black, M., and LeRoy, S., 101-125. A report by the Southwest Climate Alliance. Washington, DC: Island Press.

Hoerling, M.P., Dettinger, M., Wolter, K., Lukas, J., Eischeid, J., Nemani, R., Liebmann, B., and Kunkel, K.E., 2013: Present Weather and Climate: Evolving Conditions. In Assessment of Climate Change in the Southwest United States: a Report Prepared for the National Climate Assessment, edited by Garfin, G., Jardine, A., Merideth, R., Black, M., and LeRoy, S., 74-100. A report by the Southwest Climate Alliance. Washington, DC: Island Press.

Steenburgh, W. J., K.T. Redmond, K.E. Kunkel, N. Doesken, R.R. Gillies, J.D. Horel, M.P. Hoerling, T.H. Painter, and R. Rasmussen, 2013: Present weather and Climate: Average Conditions. In Assessment of Climate Change in the Southwest United States: a Report Prepared for the National Climate Assessment, edited by Garfin, G., Jardine, A., Merideth, R., Black, M., and LeRoy, S., 56-73. A report by the Southwest Climate Alliance. Washington, DC: Island Press.

Peterson, T.C., R.J. Heim, Jr., R. Hirsch, D.P. Kaiser, H. Brooks, N.S. Diffenbaugh, R.M. Dole, J.P. Giovannettone, K. Guiguis, T.R. Karl, R.W. Katz, K.E. Kunkel, D. Lettenmaier, G.J. McCabe, C.J. Paciorek, K. Ryberg, S. Schubert, V.B.S. Silva, B.C. Stewart, A.V. Vecchia, G. Villarini, R.S. Vose, J. Walsh, D. Wolock, K. Wolter, C.A. Woodhouse, M. Wehner, and D. Wuebbles, 2013:  Monitoring and understanding changes in heat waves, cold waves, floods and droughts in the United States: State of knowledge. Bull. Amer. Meteor. Soc., 94, 821-834.

Kunkel, K.E., T.R. Karl, D.R. Easterling, K. Redmond, J. Young, X. Yin, and P. Hennon, 2013: Probable maximum precipitation (PMP) and climate change. Geophys. Res. Lett., 40, doi:10.1002/grl.50334.

Kunkel, K.E., T.R. Karl, H. Brooks, J. Kossin, J. Lawrimore, D. Arndt, L. Bosart, D. Changnon, S.L. Cutter, N. Doesken, K. Emanuel, P.Ya. Groisman, R.W. Katz, T. Knutson, J. O’Brien, C. J. Paciorek, T. Peterson, K. Redmond, D. Robinson, J. Trapp, R. Vose, S. Weaver, M. Wehner, K. Wolter, D. Wuebbles, 2013: Monitoring and understanding changes in extreme storms: state of knowledge. Bull. Amer. Meteor. Soc., 94, 499-514, doi: DOI

Kunkel, K.E, L.E. Stevens, S.E. Stevens, L. Sun, E. Janssen, D. Wuebbles, J. Rennells, A. DeGaetano, and J.G. Dobson, 2013: Part 1. Climate of the Northeast U.S., NOAA Technical Report NESDIS 142-1, 80 pp.

Kunkel, K.E, L.E. Stevens, S.E. Stevens, L. Sun, E. Janssen, D. Wuebbles, C.E. Konrad II, C.M. Fuhrman, B.D. Keim, M.C. Kruk, A. Billet, H. Needham, M. Schafer, and J.G. Dobson, 2013: Part 2. Climate of the Southeast U.S., NOAA Technical Report NESDIS 142-2, 95 pp.

Kunkel, K.E, L.E. Stevens, S.E. Stevens, L. Sun, E. Janssen, D. Wuebbles, S.D. Hilberg, M.S. Timlin, L. Stoecker, N.E. Westcott, and J.G. Dobson, 2013: Part 3. Climate of the Midwest U.S., NOAA Technical Report NESDIS 142-3, 96 pp.

Kunkel, K.E, L.E. Stevens, S.E. Stevens, L. Sun, E. Janssen, D. Wuebbles, M.C. Kruk, D.P. Thomas, M. Shulski, N. Umphlett, K. Hubbard, K. Robbins, L. Romolo, A. Akyuz, T. Pathak, T. Bergantino, and J.G. Dobson, 2013: Part 4. Climate of the U.S. Great Plains, NOAA Technical Report NESDIS 142-4, 83 pp.

Kunkel, K.E, L.E. Stevens, S.E. Stevens, L. Sun, E. Janssen, D. Wuebbles, K.T. Redmond, and J.G. Dobson, 2013: Part 5. Climate of the Southwest U.S., NOAA Technical Report NESDIS 142-5, 79 pp.

Kunkel, K.E, L.E. Stevens, S.E. Stevens, L. Sun, E. Janssen, D. Wuebbles, K.T. Redmond, and J.G. Dobson, 2013: Part 6. Climate of the Northwest U.S., NOAA Technical Report NESDIS 142-6, 76 pp.

Stewart, B.C., K.E. Kunkel, L.E. Stevens, L. Sun, and J.E. Walsh, 2013: Part 7. Climate of Alaska, NOAA Technical Report NESDIS 142-7, 61 pp.

Keener, V.W., K. Hamilton, S.K. Izuka, K.E. Kunkel, L.E. Stevens, and L. Sun, 2013: Part 8. Climate of the Pacific Islands, NOAA Technical Report NESDIS 142-8, 45 pp.

Kunkel, K.E, L.E. Stevens, S.E. Stevens, L. Sun, E. Janssen, D. Wuebbles, and J.G. Dobson, 2013: Part 9. Climate of the Contiguous United States, NOAA Technical Report NESDIS 142-9, 78 pp.

2012

Kunkel, K.E., 2012: Uncertainties in Observed Changes in Climate Extremes. In Extremes in a Changing Climate – Detection, Analysis & Uncertainty. A.AghaKouchak, D. Easterling, K. Hsu, S. Shubert, and S. Sorooshian (Eds.), Springer, 423pp, 287-307.

Karl, T.R. B.E. Gleason, M.J. Menne, J.R. McMahon, R.R. Heim, Jr, M.J. Brewer, K.E. Kunkel, D.S. Arndt, J.L. Privette, J.J. Bates, P.Y. Groisman, and D.R. Easterling, 2012: U.S. temperature and drought: Recent anomalies and trends. EOS, 93, 473-474.

Kunkel, K.E., D.R. Easterling, D.A.R. Kristovich, B. Gleason, L. Stoecker, and R. Smith, 2012: Meteorological causes of the secular variations in observed extremeprecipitation events for the conterminous United States. J. Hydromet., 13, 1131-1141.

Liang, X.-Z., M. Xu, X. Yuan, T. Ling, H.I. Choi, F. Zhang, L. Chen, S. Liu, S. Su, F. Qiao, Y. He, J.X.L. Wang, K.E. Kunkel, W.Gao, E. Joseph, V. Morris, T.-W. Yu, J. Dudhia, and J. Michalakes, 2012: Regional Climate-Weather Research and Forecasting Model (CWRF). Bull. Amer. Meteor. Soc.93, 1363-1387.

Liang, X.-Z., M. Xu, W. Gao, K.R. Reddy, K.E. Kunkel, D.L. Schmoldt, and A.N. Samel, 2012: Physical modeling of U.S. cotton yields and climate stresses during 1979-2005. Agronomy Journal, 104, 675-683, doi:10.2134/agronj2011.0251.

2011

Liang, X.-Z., M. Xu, W. Gao, K.R. Reddy, K.E. Kunkel, D.L. Schmoldt, and A.N. Samel, 2011: A distributed growth model developed from GOSSYM and its parameter determination. Agronomy Journal, 104, 661-674, doi: 10.2134/agronj2011.0250.

Westcott, N.E., S.D. Hilberg, R.L. Lampman, B.W. Alto, A. Bedel, E.J. Muturi, H. Glahn, M. Baker, K.E. Kunkel, and R.J. Novak, 2011:  Predicting the seasonal shift in mosquito populations preceding the onset of the West Nile Virus in central Illinois.  Bull. Amer. Meteor. Soc., 92, 1173-1180.

2010

Kunkel, K.E., D. Easterling, D.A.R. Kristovich, B. Gleason, L. Stoecker, and R. Smith, 2010:  Recent increases in U.S. heavy precipitation associated with tropical cyclones.  Geophys. Res. Lett., 37, L24706, 4 pp., doi:10.1029/2010GL045164.

Kunkel, K.E., X.-Z. Liang, and J. Zhu, 2010:  Regional climate model projections and uncertainties of U.S. summer heat waves.  J. Climate, 23, 4447–4458.

Angel, J.R. and K. E. Kunkel, 2010: The response of Great Lakes water levels to future climate scenarios with an emphasis on Lake Michigan.  J. Great Lakes Res., 36, 51–58.

National Climate Assessment Scientific Support Activities

BACKGROUND

NOAA is participating in the high-level, visible, and legally mandated National Climate Assessment (NCA) process, which will be responsive to greater emphasis on user-driven science needs under the auspices of the US Global Change Research Program (USGCRP). National climate assessments are intended to advance the understanding of climate science in the larger social, ecological, and policy systems to provide integrated analyses of impacts and vulnerability. NOAA's National Climatic Data Center (NCDC) and many parts of NOAA have provided leadership on climate assessment activities for over a decade. A renewed focus on national and regional climate assessments to support improved decision-making across the country continues to emerge. Decisions related to adaptation at all scales as well as mitigation and other climate-sensitive decisions will be supported through an assessment design that is collaborative, authoritative, responsive, and transparent. NOAA is working through an interagency process and investing in partnerships across many scales to support this comprehensive assessment activity.

To support these activities, CICS has formed a technical support unit (TSU). Within the TSU, a group focused on scientific support has been assembled, consisting of a lead senior scientist (Kenneth Kunkel), a deputy scientist (Liqiang Sun), a support scientist (Laura Stevens), and a software engineer (Andrew Buddenberg). The Lead Senior Scientist provides scientific oversight for the development of NOAA’s assessment services, focusing on a contribution to the National Climate Assessment and, in support of the National Climate Assessment and in conjunction with NOAA and other agency expertise, providing scientific oversight and guidance to coordinate and implement distributed and centralized high-resolution modeling capabilities.

ACCOMPLISHMENTS

During FY13, there were several rounds of revisions of the Third National Climate Assessment in response to several rounds of reviews. These include public comments, two reviews by a National Research Council panel, and two rounds of government review. As one of the lead authors of the climate science sections, Kunkel responded to many of the comments on those sections, with text and graphics revisions and composing responses to these comments. There were also comments on the climate science portions of the other chapters, many of which were addressed by Kunkel. The other members of the science team provided substantial support to this effort by updating analyses and graphics and producing metadata on the graphics.

One major effort was the updating of a number of the graphics in response to the availability of a new statistically downscaled data set (1/8 degree-CONUS Daily Downscaled Climate Projections) produced for the U.S. Geological Survey by Katharine Hayhoe and colleagues. This new data set has statistical properties that better reproduce the climatology of daily observations. Updated maps were produced for several of the regional chapters, and some of the sectoral chapters. Another important update was of a graphic showing the range of model-simulated future projections for high and low scenarios (Fig. 1). This update required an analysis of CMIP3 and CMIP5 model simulations and the production of a more-easily understood graphic.

Metadata for a number of the key climate science figures produced by the TSU were compiled and input by the science team to the web system that will make these data available once the report is published. Substantial analysis of the CMIP5 model simulations was conducted. This will be summarized in an upcoming report.

Figure 1: Comparison of climate model simulations of historical and future global temperature changes for high (SRES A2 and RCP 8.5) and low (SRES B1 and RCP 2.6) emissions scenarios. Left graph shows climate model simulations from the Coupled-Model Intercomparison Project Phase 3 (CMIP3) and right graph shows simulations from CMIP Phase 5. Shading indicates the 5 to 95 percentile range.

All project deliverables (documentation and software) and milestones have been accomplished as planned.

PLANNED WORK

  • Publish a report comparing CMIP3 and CMIP5 climate simulations for the NCA regions
  • Lead author on climate change and health report
  • Complete papers on analysis of historical observations, including the probability distribution of monthly temperature, time of observation effects on extreme precipitation trends, day of the week signals in extreme precipitation, and the effect of the changeover to MMTS on extreme temperature trends

PUBLICATIONS

  • Peterson, T.C., T.R. Karl, J.P. Kossin, K.E. Kunkel, J.H. Lawrimore, J.R. McMahon, R.S. Vose and X. Yin, 2014: Changes in weather and climate extremes: State of knowledge relevant to air and water quality in the United States. Journal of the Air & Waste Management Association, 64,184-197, DOI:10.1080/10962247.2013.851044.
  • Lawrimore, J., T.R. Karl, M. Squires, D.A. Robinson, and K.E. Kunkel, 2013: Trends and variability in severe snowstorms east of the Rocky Mountains. J. Hydromet., submitted.
  • Janssen, E., D.J. Wuebbles, K.E. Kunkel, S.C. Olsen, and A. Goodman, 2013: Observed and modeled trends and projections of extreme precipitation over the contiguous United States. Earth’s Future, accepted.
  • Vose, R.S., S. Applequist, M.A. Bourassa, S.C. Pryor, R.J. Barthelmie, B. Blanton, P.D. Bromirski, H.E. Brooks, A.T. DeGaetano, R.M. Dole, D.R. Easterling, R.E. Jensen, T.R. Karl, R.W. Katz, K. Klink, M.C. Kruk, K.E. Kunkel, M.C. MacCracken, T.C. Peterson, K.Shein, B.R. Thomas, J.E. Walsh, X.L. Wang, M.F. Wehner, D.J. Wuebbles, and R.S. Young, 2012: Monitoring and understanding changes in Extremes: Extratropical storms, winds, and waves. Bull. Amer. Meteor. Soc., accepted.
  • Wuebbles, D.W., G. Meehl, K. Hayhoe, T. R. Karl, K. Kunkel, B. Santer, M. Wehner, B. Colle, E. M. Fischer, R. Fu, A. Goodman, E. Janssen, H. Lee, W. Li, L. N. Long, S. Olsen, A. Seth, J. Sheffield, and L. Sun, 2013: CMIP5 climate model analyses: Climate extremes in the United States. Bull. Amer. Meteor. Soc., accepted
  • Peterson, T.C., R.J. Heim, Jr., R. Hirsch, D.P. Kaiser, H. Brooks, N.S. Diffenbaugh, R.M. Dole, J.P. Giovannettone, K. Guiguis, T.R. Karl, R.W. Katz, K.E. Kunkel, D. Lettenmaier, G.J. McCabe, C.J. Paciorek, K. Ryberg, S. Schubert, V.B.S. Silva, B.C. Stewart, A.V. Vecchia, G. Villarini, R.S. Vose, J. Walsh, D. Wolock, K. Wolter, C.A. Woodhouse, M. Wehner, and D. Wuebbles, 2013: Monitoring and understanding changes in heat waves, cold waves, floods and droughts in the United States: State of knowledge. Bull. Amer. Meteor. Soc., 94, 821-834.
  • Kunkel, K.E., T.R. Karl, H. Brooks, J. Kossin, J. Lawrimore, D. Arndt, L. Bosart, D. Changnon, S.L. Cutter, N. Doesken, K. Emanuel, P.Ya. Groisman, R.W. Katz, T. Knutson, J. O’Brien, C. J. Paciorek, T. Peterson, K. Redmond, D. Robinson, J. Trapp, R. Vose, S. Weaver, M. Wehner, K. Wolter, D. Wuebbles, 2013: Monitoring and understanding changes in extreme storms: state of knowledge. Bull. Amer. Meteor. Soc., 94, 499-514,doi: http://dx.doi.org/10.1175/BAMS-D-12-00066.1.
  • Wuebbles, D.J., K.E. Kunkel, M. Wehner, and Z. Zobel, 2014: Severe weather in the United States under a changing climate. EOS, accepted.

DELIVERABLES

  • Publication of papers summarizing the extremes workshops;
  • Updated graphics for NCA report; and
  • Compiled metadata for key science chapter graphics.

     

PRESENTATIONS

  • Kunkel, K.E., 2014: Extreme Precipitation Trend Estimation in Conterminous United States (CONUS), poster paper, Donald R. Johnson Symposium, Annual Meeting of the American Meteorological Society, Atlanta, GA (6 February).
  • Kunkel, K.E., 2014: Observed Trends in Extreme Precipitation: Illinois and Beyond, invited talk, Stanley A. Changnon Symposium, Annual Meeting of the American Meteorological Society, Atlanta, GA (4 February).
  • Kunkel, K.E., 2014: Historical Trends and Future Projections of Extreme Climate Conditions for the U.S. National Climate Assessment, Annual Meeting of the American Meteorological Society, Atlanta, GA (4 February).
  • Kunkel, K.E., 2014: What are the Innovations in Science and Scenarios for this and Future Assessments, invited talk, National Council for Science and Engineering 14th National Conference, Washington, DC (28 January).
  • Kunkel, K.E., 2013: Observed Trends in Extreme Precipitation in the U.S., invited talk, 2013 Fall Meeting of the American Geophysical Union, San Francisco, CA (13 December).
  • Kunkel, K.E., 2013: U.S. Regional Extreme Climate Conditions in CMIP5 Simulations, invited talk, 2013 Fall Meeting of the American Geophysical Union, San Francisco, CA (12 December).
  • Kunkel, K.E., 2013: National Climate Assessment Climate Modeling and Downscaling, invited talk, Scoping Workshop for the National Climate Assessment (NCA) Special Report on Climate Change and Health, Washington, DC (21 November).
  • Kunkel, K.E., 2013: U.S. Climate Scenarios, invited talk, Second Nature webinar on “Understanding Climate Impacts: Using Tools and Resources to Prepare Your Campus for a Changing Climate” (20 November).
  • Kunkel, K.E., 2013: Extreme Precipitation Events: Data Issues and Meteorological Causes, invited talk, U.S. CLIVAR Workshop: Analyses, Dynamics, and Modeling of Large Scale Meteorological Patterns Associated with Extreme Temperature and Precipitation Events, Berkeley, CA (20 August).
  • Seyller, E., K.E. Kunkel, and L.E. Stevens, 2013: Regional Climate Trends and Scenarios for the United States, GreenGov Workshop on Climate Science and Adaptation Planning, Washington, D.C. (2 August).
  • Kunkel, K.E., 2013: National Climate Assessment: Potential CDR Program Contributions, invited talk, NOAA Climate Data Record Annual Meeting, Asheville, NC (30 July).
  • Kunkel, K.E., 2013: Climate Extremes Research: Recent Findings and New Directions, invited talk, Snowmass 2013 Integrated Climate Change Impacts Session, Energy Modeling Forum, Snowmass, CO (24 July).
  • Kunkel, K.E., 2013: An Assessment of Extreme Weather and Climate Events, invited talk, Summer Meeting of the Federation of Earth System Information Providers, Raleigh, NC (11 July).
  • Kunkel, K.E., 2013: Extreme Weather and Climate Events, invited talk, Tokio Marine’s Eighth Summit on Global Warming and Climate Change, Atlanta, GA (28 June).
  • Kunkel, K.E., 2013: Observed Trends and Future Projections of Drought, invited talk, Advisory Committee on Water Information, webinar (27 June).
  • Kunkel, K.E., 2013: Observed Trends and Future Projections of Extremes, invited talk, 35th MIT Global Change Forum, Cambridge, MA (5 June).
  • Kunkel, K.E., 2013: Climate Change and Extreme Weather and Climate Events, invited talk, Executive Forum for Business and Climate, Asheville, NC (4 June).
  • Kunkel, K.E., 2013: Observed Trends and Future Projections of Extremes, invited talk, Advisory Committee on Water Information, webinar (30 May).
  • Kunkel, K.E., 2013: Analysis of Historical and Future Snow Conditions for the National Climate Assessment, Western Snow Conference, Jackson, Wyoming (16 April).
  • Kunkel, K.E., 2014: National Climate Assessment: An Overview, A-B Tech Community College Environmental Biology class, Asheville, NC, (25 March).
  • Kunkel, K.E., 2014: Extreme Precipitation Trends and Future Changes in Urban Areas Due to Global Warming, invited talk, International Symposium on Diagnosis and Early Warning of Urban Weather/Climate Extremes, Nanjing, China, (19 March).

Trends in Extra-tropical Cyclone Occurrence

BACKGROUND

ETCs are large-scale, non-tropical, low-pressure storm systems that typically develop along a frontal boundary between air masses of contrasting temperature. The ETC is the principal atmospheric phenomenon through which sensible and latent heat fluxes are exchanged between the subtropical and polar regions. These large-scale cyclonic storms are the major feature of mid-latitude weather during the colder times of the year and often have severe weather associated with them. These storms can produce large snowfall amounts that, together with high winds, result in blizzard conditions, large waves leading to coastal erosion, and severe convective events with lightning and tornadoes. In fact, these storms (or their absence in the case of drought) are responsible for many of the extreme weather types experienced at mid- and high-latitudes. ETCs are ubiquitous throughout the year, but tend to be stronger and located more equatorward in the cold season. Future changes in extreme weather in mid- to high-latitudes will likely involve changes in the frequency, intensity, and tracks of ETCs.

A number of recent studies focused on the Northern Hemisphere have documented a significant poleward shift of the storm track in both the Pacific and Atlantic Ocean basins, a decrease in ETC frequency in mid-latitudes, and a corresponding increase in ETC activity at higher latitudes for the latter half of the 20th century. Future climate warming may lead to a decrease in polar low activity. A new analysis of surface pressure data has extended the availability of pressure field data from the mid-20th century as used in previous studies, back to the late 19th Century. We have used this new 20th Century Reanalysis (20CR) data set to extend the analysis of ETC occurrence in the Northern Hemisphere to the period 1871-2007.

ACCOMPLISHMENTS

Previous work found some notable trends in ETC activity. From 1871 to 2010, statistically significant trends in high latitude ETC activity were found in the Pacific sector (downward) and in the Europe and Asia sectors (upward). Upward, statistically significant trends were found for all mid-latitude sectors (bottom panels). These results imply a substantial equator-ward shift over the North American and Pacific sectors. The main focus of effort this year was to address issues of uncertainty. Specifically, how robust are these observed trends in the context of changes over time in the availability of pressure observations to drive the reanalysis model.

The availability of a 56-ensemble set of reanalysis output provides an opportunity to quantify the uncertainties. This project analyzed the variability of cyclone tracks and computed the average variability over consecutive 5-year periods. Two of the periods are illustrated in Figs. 1 and 2. In the early part of the reanalysis period, variability is quite high over the North Pacific and much of the high latitude area, indicating greater uncertainty. These coincide with areas of low data availability. By contrast, variability is quite low, indicating lower uncertainty, over most land areas and the North Atlantic. By the middle of the 20th Century (e.g. Fig. 2), data availability has increased in most areas. In the North Pacific and high latitudes, variability of ETC tracks has decreased by about a factor of three, indicating substantially lower uncertainties.

The analysis results were interpreted to mean that the ETC counts over the North Pacific are probably reliable back to the 1920s or so and back to the 1930s for high latitude locations except for the Arctic Ocean, but before those points in time the uncertainties are large enough to call into question the reality of the analyzed temporal variations. For mid-latitude land areas and the North Atlantic, estimates of ETC activity can probably be considered reliable back to the 1890s.

Figure 1: Variability in cyclone track location (contours) for the period 1911-1915. Color shading shows the percentage of days with at least one pressure observation in the grid box.

Figure 2: Variability in cyclone track location (contours) for the period 1946-1950. Color shading shows the percentage of days with at least one pressure observation in the grid box. Compared to 1911-1915 (Fig. 1), variability is much reduced in the North Pacific and high latitudes

A web site is being developed that will show the results of this project. Specifically, it will provide maps of individual ETC tracks and climatologies for various periods.

PLANNED WORK

  • Complete and submit a paper on reliable periods of ETC activity
  • Complete web site providing maps of ETC tracks

PUBLICATIONS

  • Vose, R.S., S. Applequist, M.A. Bourassa, S.C. Pryor, R.J. Barthelmie, B. Blanton, P.D. Bromirski, H.E. Brooks, A.T. DeGaetano, R.M. Dole, D.R. Easterling, R.E. Jensen, T.R. Karl, R.W. Katz, K. Klink, M.C. Kruk, K.E. Kunkel, M.C. MacCracken, T.C. Peterson, K.Shein, B.R. Thomas, J.E. Walsh, X.L. Wang, M.F. Wehner, D.J. Wuebbles, and R.S. Young, 2012:  Monitoring and understanding changes in Extremes: Extratropical storms, winds, and waves. Bull. Amer. Meteor. Soc., accepted.
  • Wuebbles, D.W., G. Meehl, K. Hayhoe, T. R. Karl, K. Kunkel, B. Santer, M. Wehner, B. Colle, E. M. Fischer, R. Fu, A. Goodman, E. Janssen, H. Lee, W. Li, L. N. Long, S. Olsen, A. Seth, J. Sheffield, and L. Sun, 2013:  CMIP5 climate model analyses: Climate extremes in the United States. Bull. Amer. Meteor. Soc., accepted.

DELIVERABLES

  • Completion of uncertainty analysis

PRESENTATIONS

  • Kunkel, K.E., 2013: Extreme Precipitation Events: Data Issues and Meteorological Causes, invited talk, U.S. CLIVAR Workshop: Analyses, Dynamics, and Modeling of Large Scale Meteorological Patterns Associated with Extreme Temperature and Precipitation Events, Berkeley, CA (20 August).