Carl Schreck

Carl Schreck

CICS-NC
NOAA's National Climatic Data Center
Veach-Baley Federal Building
151 Patton Avenue
Asheville, NC 28801-5001
 Telephone: +1 828.257.3140
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Dr. Schreck completed his Ph.D. in 2010 at the University at Albany, State University of New York. His research investigates tropical weather and its impacts around the globe. In particular, he focuses on identifying and predicting the Madden–Julian Oscillation (MJO) and equatorial waves. Dr. Schreck engages with partners in the energy industry to explore how these systems can improve long-range forecasts of temperatures over the United States. He also uses NCDC’s International Best Track Archive for Climate Stewardship (IBTrACS) to explore the relationships between climate variability and tropical cyclones. As part of that work, Dr. Schreck is CICS-NC’s lead investigator on CycloneCenter.org, which invites citizen scientists to analyze historical tropical cyclone images.

Dr. Schreck joined CICS-NC in August 2010 as a Postdoctoral Fellow and has since transitioned to a Research Associate position in November 2012. He serves on the Climate Prediction Center’s global tropical hazards forecast team and as an Associate Editor for Monthly Weather Review.

2013
Schreck, C. J., L. Shi, J. P. Kossin, and J. J. Bates, 2013: Identifying the MJO, equatorial waves, and their impacts using 32 years of HIRS upper-tropospheric water vapor. J. Climate, 26, 1418–1431, doi:10.1175/JCLI-D-12-00034.1.
2012
Ventrice, M. J., C. D. Thorncroft, and C. J. Schreck, 2012: Impacts of convectively coupled Kelvin waves on environmental conditions for Atlantic tropical cyclogenesis. Mon. Wea. Rev., 140, 2198–2214, doi:10.1175/MWR-D-11-00305.1.
 
Kruk, M. C., C. J. Schreck, and Hennon, Paula A., 2012: [The Tropics] Eastern North Pacific basin [in “State of the Climate in 2011”]. Bull. Amer. Meteor. Soc., 93, S105–S107, doi:10.1175/2012BAMSStateoftheClimate.1.
 
Aiyyer, A., A. Mekonnen, and C. J. Schreck, 2012: Projection of tropical cyclones on wavenumber-frequency filtered equatorial waves. J. Climate, 25, 3653–3658, doi:10.1175/JCLI-D-11-00451.1.
 
Schreck, C. J., J. Molinari, and A. Aiyyer, 2012: A global view of equatorial waves and tropical cyclogenesis. Mon. Wea. Rev., 140, 774-788, doi:10.1175/MWR-D-11-00110.1.
2011
Schreck, C. J., and J. Molinari, 2011: Tropical cyclogenesis associated with Kelvin waves and the Madden–Julian oscillation, Mon. Wea. Rev., 139, 2723-2734, doi:10.1175/MWR-D-10-05060.1.
 
Schreck, C. J., J. Molinari, and K. I. Mohr, 2011: Attributing tropical cyclogenesis to equatorial waves in the western North Pacific. J. Atmos. Sci.68, 195-209, doi:10.1175/2010JAS3396.1.  
2009
Schreck, C. J., and J. Molinari, 2009: A case study of an outbreak of twin tropical cyclones. Mon. Wea. Rev.137, 863-875, doi:10.1175/2008MWR2541.1.  
 
Roundy, P. E., and C. J. Schreck, 2009: A combined wave-number–frequency and time-extended EOF approach for tracking the progress of modes of large-scale organized tropical convection. Quart. J. Roy. Meteor. Soc.135, 161-173, doi:10.1002/qj.356.  
 
Roundy, P. E., C. J. Schreck, and M. A. Janiga, 2009: Contributions of convectively coupled equatorial Rossby waves and Kelvin waves to the real-time multivariate MJO Indices. Mon. Wea. Rev.137, 469-478, doi:10.1175/2008MWR2595.1.  
2004
Schreck, C. J., and F. H. M. Semazzi, 2004: Variability of the recent climate of eastern Africa. Int. J. Climatol., 24, 681-701, doi:10.1002/joc.1019.  

The Madden–Julian Oscillation and Tropical Cyclones in the Western Hemisphere

EXECUTIVE SUMMARY

This research uses novel satellite datasets to investigate tropical intra-seasonal variability, including the Madden–Julian Oscillation (MJO) and equatorial waves. Particular emphasis is placed on the relationship between the MJO and tropical cyclone activity in the Western Hemisphere. Daily monitoring of satellite-derived MJO signals provides a valuable tool for predicting tropical variability in the 5–30 day range.

BACKGROUND

The MJO has frequently been identified with proxies for convection such as outgoing longwave radiation (OLR). These data are suitable for the Eastern Hemisphere where deep tropical convection is commonplace. However, the convective signal becomes weaker in the Western Hemisphere, even as the signal persists in the upper troposphere. Inter-satellite calibration techniques have recently produced a homogeneous 32-year dataset of upper tropospheric water vapor (UTWV) from the high-resolution infrared radiation sounder (HIRS). These data are being used to develop a global view of the MJO.

The MJO significantly affects tropical cyclone activity around the globe. This project uses the UTWV data to identify how the MJO influences tropical cyclogenesis over the eastern North Pacific and the North Atlantic. Possible mechanisms include the local enhancement of convection and low-level vorticity, amplification of easterly waves, remote impacts on the vertical wind shear, and baroclinic effects. These issues are being explored through a case study of the record breaking Atlantic hurricane season in 2005.

Tropical cyclone activity is diagnosed using the International Best Track Archive for Climate Stewardship (IBTrACS) from NOAA’s National Climatic Data Center. IBTrACS combines tropical cyclone data from numerous international agencies. Operational procedures have evolved through time, and they vary greatly between agencies. Research is ongoing to document and mitigate these heterogeneities in the record.

ACCOMPLISHMENTS

A climatology of the MJO and equatorial waves in UTWV has been submitted to the Journal of Climate. Spectral analysis shows that the MJO and equatorial waves stand out above the low-frequency background in UTWV, similar to previous findings with OLR. The MJO and equatorial Rossby waves are associated with a greater fraction of the total variance in UTWV than in OLR. In the subtropics, UTWV identifies the subsidence drying that occurs poleward of the MJO’s convection. These signals are absent from OLR. For equatorial Rossby waves, the variance is more equatorially symmetric and less seasonally dependent in UTWV than in OLR. Kelvin waves, on the other hand, are overshadowed in UTWV by the extratropical Rossby waves that share similar propagation characteristics. These results demonstrate the utility of UTWV, in concert with OLR, for identifying tropical intra-seasonal variability.

A new website (http://monitor.cicsnc.org/mjo/) was developed and implemented for daily monitoring of the MJO and equatorial waves. This website applies established diagnostics to both UTWV and OLR. It has been tailored to meet the needs of forecasters at NOAA’s Climate Prediction Center (CPC). Special diagnostics have also been developed to support forecasts for the DYNAMO (Dynamics of the MJO) field campaign that was conducted over the Indian Ocean from October 2011 to March 2012.

Figure 1. Longitude–time Hovmšller diagrams of OLR (left) and UTWV (right) anomalies relative to their respective 1979–2011 daily climatologies. Both variables are averaged 15°S–15°N. Heavy black lines identify the convective (solid) and suppressed (dashed) phases of the MJO.

Figure 1 illustrates two longitude–time Hovmšller diagrams from the monitoring website. The left panel shows OLR, while the right panel presents UTWV brightness temperatures. In both cases, the shading indicates anomalies relative to their respective 32-year daily climatologies. Negative anomalies (cool shading) correspond to cold cloud tops in OLR and enhanced upper-level moisture in UTWV. In both cases, these negative values are generally associated with ascent.

Fortunately for the DYNAMO field campaign, the MJO was particularly active during October–December 2011. Tropical convection varies on a variety of time scales, but the heavy black lines in Fig. 1 roughly identify the convective (solid) and subsiding (dashed) phases of the MJO. The DYNAMO campaign was centered near 60°E where MJO’s convection initiates before it moves eastward. In OLR (left panel), the MJO signals weaken as they traverse the eastern Pacific (150°W–60°W). UTWV (right panel), on the other hand, tracks the signals more continuously around the globe. The positive and negative UTWV anomalies also have similar magnitudes, unlike OLR. UTWV is more sensitive to the subsiding branches of the tropical circulation, as demonstrated by the large positive (warm colors) anomalies near the dateline in December. These diagnostics provided a valuable forecasting tool during the field campaign.

The record-breaking 2005 Atlantic hurricane season provided an ideal testbed to examine the relationship between the MJO and tropical cyclones in the Western Hemisphere. During August, tropical cyclone development gradually shifted eastward from the eastern Pacific to the western Atlantic with the passage of the MJO’s convective envelope. This envelope circumnavigated the globe, and the pattern repeated in September–October. Ongoing research is examining the modulation of convection, low-level vorticity, and vertical wind shear by this MJO event. UTWV also indicates a connection between the MJO signals in the Northern Hemisphere and extratropical systems in the Southern Hemisphere. These relationships and their impacts on tropical cyclone activity will be explored further.

Research is also underway to produce a global climatology of tropical cyclones using IBTrACS. IBTrACS comprises historical tropical cyclone best-track data from numerous sources around the globe, including all of the Regional Specialized Meteorological Centers (RSMCs). It represents the most complete amalgamation of tropical cyclone data compiled to date. IBTrACS offers a unique opportunity to revisit the global climatology of tropical cyclones. This research is exploring the mean annual global tropical cyclone activity as well as interannual variability within each basin. Discrepancies between sources in IBTrACS are being identified in order to motivate future reanalysis efforts.

PLANNED WORK

  • Complete the case study of the MJO during the 2005 Atlantic Hurricane season and submit it for publication.
  • Use estimates of total precipitable water from the Special Sensor Microwave Imager/Sounder (SMMIS) to investigate the evolution of low-level moisture during MJO onset.
  • Use IBTrACS to produce a global climatology of tropical cyclones for the period 1981–2010. Particular emphasis will be placed on uncertainties between data sources and heterogeneities in time.

PUBLICATIONS

Schreck, C. J., L. Shi, J. P. Kossin, and J. J. Bates, 2011: Tropical intraseasonal variability in outgoing longwave radiation and upper tropospheric water vapor. J. Climate, Submitted.

Ventrice, M. J., C. D. Thorncroft, and C. J. Schreck, 2011: Impacts of convectively coupled Kelvin waves on environmental conditions for Atlantic tropical cyclogenesis. Mon. Wea. Rev., In Press.

Aiyyer, A., A. Mekonnen, and C. J. Schreck, 2012: Projection of tropical cyclones on wavenumber-frequency filtered equatorial waves. J. Climate, In Press.

Schreck, C. J., J. Molinari, and A. Aiyyer, 2012: A global view of equatorial waves and tropical cyclogenesis. Mon. Wea. Rev., 140, 774-788.

PRESENTATIONS

  • Schreck, C. J., 2011: The Madden–Julian Oscillation and Equatorial Waves in Upper Tropospheric Water Vapor. Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC, September 2011.
  • Schreck, C. J., 2011: Upper Tropospheric Water Vapor: A New Dataset for Monitoring the Madden–Julian Oscillation. NOAA’s Climate Prediction Center, Camp Springs, MD, August 2011.
  • Schreck, C. J., J. Kossin, K. Knapp, and L. Shi, 2011: Continuing development of climate information records at NOAA's National Climatic Data Center. World Climate Research Programme Open Science Conference, 24–28 October 2011, Denver, CO.
  • Schreck, C. J., J. Kossin, and L. Shi, 2011: The Madden–Julian Oscillation and equatorial waves in upper tropospheric water vapor. 8th Annual Cooperative Research (CoRP) Science Symposium, 17-18 August 2011, Asheville, NC.
  • Schreck, C. J., 2011: Best track continuity. 2nd IBTrACS Workshop, 11-13 April 2011, Honolulu, HI.
  • Schreck, C. J., 2011: Best track data in synoptic studies: What is a tropical cyclone? 2nd IBTrACS Workshop, 11-13 April 2011, Honolulu, HI.

OTHER (e.g., awards; outreach; deliverables...)

  • Developed monitoring website (http://monitor.cicsnc.org/mjo/) to increase user engagement
  • Contributed to NOAA/CPC’s weekly Madden–Julian Oscillation and Global Tropical Hazards Assessment
  • Provided additional forecasting support to NOAA/CPC for the DYNAMO field campaign