Richard (Rit) Carbone

Director TIIMES & Senior Scientist
TIIMES

Contact Information:
PO Box 3000, Boulder, CO 80307-3000
Office: FL2 - 3085
Telephone: 303-497-8626
Email: carbone@ucar.edu
Home Page

Project Summary:

Click on picture to view the entire figure.

Diurnal radar echo frequency of occurrence, JJA, expressed as % of days within a given UTC hour that precipitation echo is present. (a) 2100 (b) 0200 (c) 0700 (d) 1300. Readers are referred to the supplementary animation, which provides a superior visualization of the continental diurnal cycle.

In addition to his varied duties as the director of the TIIMES institute, Rit Carbone also finds time to continue to pursue his research interests.

Rainfall Occurrence in the United States Warm Season: The Diurnal Cycle

R.E. Carbone and J.D. Tuttle
Submitted to the "Understanding Diurnal Variability of Precipitation through Observations and Models" special issue of the Journal of Climate

Click on picture to view the entire figure.

Diurnal radar echo frequency of occurrence in the continental domain, JJA, with the southern boundary of the domain raised from 30N to 33N. This change reduces the influence of rainfall having a coastal breeze origin. (a) 1997-2000 (after C2) (b) 1996-2007. Longer period of record yields a substantially similar diurnal pattern.

Abstract

The diurnal occurrence of warm season rainfall over the U.S. mainland is examined, particularly in light of forcings at multiple scales.  The analysis is based on a radar dataset of 12 seasons duration covering the U.S. mainland from the continental divide eastward.  The dataset resolves 2 km features at 15 min intervals, thus providing a detailed view of both large scale and regional scale diurnal patterns, as well as the statistics of events underlying these patterns.  The results confirm recent findings with respect to the role of propagating rainfall systems and the high frequency at which these are excitated by sensible heating over elevated terrain.  Between the Rockies and the Appalachians, ~ 60% of mid-summer rainfall occurs in this manner. 

Most rainfall in the central U.S. is nocturnal and may be attributed to three main forcings: 1) The passage of eastward-propagating rainfall systems with origin near the continental divide at 105W;  2) A nocturnal reversal of the mountain-plains solenoid, which is associated with widespread ascent over the Plains;  and 3) The transport of energetic air and moisture convergence by the Great Plains low level jet.

Other features of interest include effects of the Appalachians, semi-diurnal signals of regional significance, and the impact of breezes along the Gulf of Mexico.  A modest effort was put forth to discern signals associated with El Nino and the Southern Oscillation. While tendencies in precipitation patterns are observed, the record is too short to draw conclusions of general significance.

Presentations:

• A mesoscale challenge presented by continental rainfall climatologies-keynote, Boulder USA, November 2006
• Concepts for a Bio-Hydro-Geosciences Division, other, Boulder USA, November 2006
• Concepts on mesoscale observations to meet multiple national needs, other, Washington D.C. USA, January 2007
• Opportunities for Collaboration between the National University of Singapore and NCAR, other, Singapore CHN, February 2007
• The diurnal cycle of warm season rainfall., San Antonio USA, January 2007
• The Institute for Multidisciplinary Earth Studies: Opportunities to participate in BEACHON, Other, Amherst USA, June 2007
• The Institute for Multidisciplinary Earth Studies: Overview for the National University of Singapore Delegation, Other, Boulder USA, April 2007
• TIIMES Institute Overview, Boulder USA, August 2007

TIIMES External Collaborators:

Kathryn Alexander, Arizona State University
Joseph Alfieri, Purdue University
Ray Anderson, University of California, Irvine
Ryan Anderson, University of Minnesota
Phil Arkin, University of Maryland
Yaxidhi Bamutaze, Makerere University
Valerie Bennington-Benesh, University of Wisconsin
Kathryn Berger, University of New Hampshire
Fredi Birsan, Indiana University
Joseph Blankinship, Northern Arizona University
Philippe Bougeault, European Centre for Medium-Range Weather Forecasts (ECMWF)
Bryan Brandel, University of Colorado
Martha Butler, The Pennsylvania State University
Mariah Carbone, University of California, Irvine
Erica Cate, University of New Hampshire
Laura Chasmer, Queens University
George Tai-Jen Chen, National Taiwan University
William Cotton, Colorado State University
K Dhanyalekshmi, Max Planck Institute for Biogeochemistry
Darren Drewry, Duke University
Ian Galbally, Commonwealth Scientific and Industrial Research Organisation (CSIRO) - Marine & Atmopsheric Research
Jordan Golinkoff, University of Montana-Missoula
Sharon Gourdji, University of Michigan
Arun Govind, University of Saskatchewan
Vanda Grubisic, Desert Research Institute
Victor Gutierrez Velez, Clark University
Sherri Heck, University of Colorado & NCAR
William Henson, McGill University
Jennifer Jensen, University of Idaho
Ranjeet John, University of Toledo
Fuu-Ming Kai, University of California, Irvine
Jenny Kao-Kniffin, University of Wisconsin
Tom Keenan, Bureau of Meteorology Research Center
Myroslava Khomik, McMaster University
Angela Kross, McGill University
Lynette Laffea, University of Colorado
Vincenzo Levizzani, Consiglio Nazionale delle Ricerche
Kendra Morliengo-Bredlau, University of Colorado
Steve Nesbitt, Colorado State University
Tomohira Oda, Osaka University of Japan
Nicholas Parazoo, Colorado State University
Matthew Parker, North Carolina State University
Alicia Peduzzi, Virginia Polytechnic Institute and State University
Augusto Pereira Filho, University of São Paulo
Wei Ren, Auburn University
Diego Riveros, Montana State University-Bozeman
Miguel Roman, Boston University
Koichi Sagaguchi, University of Arizona
Cheney Shreve, University of Virginia
Eric Smith, Goddard Space Flight Center (GSFC) - NASA
Oliver Sonnentag, University of Toronto
Shannon Spencer, Colorado State University
Ann Thijs, University of Texas at Austin
Erico Tomelleri, Max Planck Institute for Biogeochemistry
Gregory Tripoli, University of Wisconsin
Rodrigo Vargas, University of California, Riverside
Chung-Chieh Wang, Chinese Culture University
Lixin Wang, University of Virginia
Sonia Wharton, University of California, Davis
Kyle Whittinghill, University of Minnesota
Stephen Wood, Monash University
Xiaojuan Yang, University of Illinois at Urbana-Champaign
Jose Zerpa, North Carolina State University

Publications:

Carbone, R. E., J. D. Tuttle, 2007: Rainfall Occurrence in the United States Warm Season: the diurnal cycle. J. Climate. (Submitted)

Lang, T. J., D. A. Ahijevych, S. W. Nesbitt, R. E. Carbone, S. A. Rutledge, R. Cifelli, 2007: Radar-observed characteristics of precipitating systems during NAME 2004. J. Climate, 20(9), 1713-1733, doi: 10.1175/JCLI4082.1.

Laing, A.G., R. E. Carbone, and V. Levizzani, 2007: The propagation of deep convection in Africa: Implications for predictability of precipitation. Quantification and Reduction of Predictive Uncertainty for Sustainable Water Resources Management (Eds. E. Boegh, H. Kunstmann, T. Wagnerer, A. Hall, L. Bastidas, S. Franks, H. Gupta, D. Rosbjerg, J. Schaake). IAHS Publ. 313, 24-32.

Levizzani, V., R. E. Carbone, R. Ginnetti, A. G. Laing, M. Masotti, S. Melani, M. Pasqui, 2007: Climatology of warm season precipitating clouds: first results for Europe and Mediterranean. Climate and Climate Change: Research Activities of the National Research Council, B. Carli, G. Cavarretta, M. Colacino, S. Fuzzi, National Research Council, Eds., 113-116.

Laing, A. G., J. Tuttle, R. Carbone, V. Levizzani, 2006: The propagation and diurnal cycle of deep convection in northern tropical Africa. Quart. J. Roy. Meteor. Soc.. (Submitted)