Sea Breeze Forecasting and Applications along the New

Sea Breeze Forecasting and Applications along the New Jersey Coast Louis Bowers, R. Dunk, J. Kohut, H. Roarty, S. Glenn, and A. Cope Rutgers University Coastal NJ SOS Ocean Meteorological Forecast Observation Component Lab

Talk Outline • The New Jersey Sea Breeze • Coastal Upwelling along the NJ Coast • Case studies: June 23 rd and July 5 th, 2000 • Impact on NWS forecasts • Future work

Sea Breezes Along the New Jersey Coast • Develops as a result of the land/sea temperature gradient Land heats faster than the ocean. 930 mb 950 mb Warm air over the land rises. Sea Breeze Cold air from over the ocean rushes in to replace it. 970 mb Delaware Onshore flow Upwelled Water Bay Breeze (58ºF) City (96ºF) Beach (90ºF) Ocean (72ºF) A closed sea breeze circulation cell develops.

Sea Breezes Along the New Jersey Coast • Develops as a result of the land/sea temperature gradient • Can occur during any month of the year Sea Breezes by Month: 1996 -2002

Sea Breezes Along the New Jersey Coast 18: 30 UTC 20: 35 UTC 22: 30 UTC 00: 25 UTC • Develops as a result of the land/sea temperature gradient • Can occur during any month of the year. • Can affect almost all of New Jersey and into SE Pennsylvania.

Sea Breezes Along the New Jersey Coast Sea Breeze Delaware Bay Breeze • Develops as a result of the land/sea temperature gradient • Can occur during any month of the year. • Can affect almost all of New Jersey and into SE Pennsylvania. • Focus for occasional severe thunderstorm development.

Sea Breezes Along the New Jersey Coast Long Beach Isl. , NJ: Year-round: 9, 000 Summer: 110, 000+ Ocean City, NJ Year-round: 15, 000 Summer: 150, 000+ Wildwood, NJ Year-round: 5, 500 Summer: 250, 000+ Census 2000 • Develops as a result of the land/sea temperature gradient • Can occur during any month of the year. • Can affect almost all of New Jersey and into SE Pennsylvania. • Focus for occasional severe thunderstorm development. • Forecast problem: Tourism and Energy

Structure of the Sea Breeze Sea breeze circulation cell initially forms 14 -16 Z June 23, 2000 2700 2400 2100 Typical inland propagation speed 1 -10 km/hour depending on geostrophic wind flow 1800 1500 meters Typical sea breeze cell depth 600 -1, 800 meters 1200 900 Sea Breeze Vertical Extent 600 300 0 Inland frontal propagation diminished by offshore 850 mb winds greater than 10 m/s (Kwiatkowski, 1999) Does not always take the coastline shape Northwest Wind South Wind Sea Breeze Front Delaware Bay Breeze Surface Temperature (C)

Sea Breeze Front as Seen by Satellite and Radar RU COOL Visible Satellite Imagery NWS Doppler Radar WSR 88 -D 2002/08/17 18: 11: 00 Sea Breeze Front Upwelling

Summer upwelling El Nino! Seasonal temperature variation is the primary signal. Is upwelling 2 nd?

Sea Surface Temperature from AVHRR Satellite * IMCS * Sandy Hook * Trenton Belmar * Tuckerton Atlantic City * * * New York Coastal Upwelling * nd Philadelphia * wi Newark SW upwelling favorable wind Upwelled Water

Modeled Effect of Bathymetric Variability on Upwelling 1 m/s current velocity Along shore subsurface deltas cause upwelling to be 3 d, not 2 d. North win d Barnegat delta LEO delta Cape May delta Song, et al. , 1999

Regional Atmospheric Modeling System Case Studies Model Specifications • Three nested grids Study area in red • Grid 1 – 32 km resolution 34 x 34 points with 40 s time step • Grid 2 – 8 km resolution 50 x 50 points with 13 s time step • Grid 3 – 2 km resolution 90 x 106 points with 4 s time step • 45 vertical levels with almost half of them below 2 km • 48 hour simulation • Used both upwelling and non-upwelling SSTs (AVHRR) • Harrington radiation scheme • Mellor and Yamada subgrid turbulence scheme • NCEP Reanalysis data for model initialization

Sea Breeze Case Study: June 23, 2000 SST from AVHRR Satellite SST used in RAMS simulation June 23 rd SSTs SST composite technique as described in S. M. Glenn and M. F. Crowley, 1997.

1400 UTC 34 2000 UTC 32 30 28 26 24 22 20 18 2000 UTC 34 32 30 28 26 24 22 20 18

Sea Breeze Case Study: July 5, 2000 Typical upwelling SST regime vs. Non-upwelling July 27, 2000 ocean surface (“upwelling turned off”) SST difference (July 5 th – July 27 th July 5 th SSTs July 27 th SSTs

Upwelling vs. Non-Upwelling SST 2 m Temp (ºC)/Upwelling SST 2300 UTC July 5, 2000 2 m Temp (ºC)/Non-Upwelling SST 2 m Temp (ºC) Sea Breeze front 5 – 10 km farther inland during upwelling SST (upper left) Sea Breeze front as shown by wind vector plot (lower left) 2 m Temp Difference (ºC) (lower right) 2300 UTC

Upwelling vs. Non-Upwelling SST What can we get from better sea breeze forecasts? • More accurate temperatures for NWS (at the coast and inland) • Savings to energy companies and consumers • Marine wind forecasts • Accurate beach forecasts -> Tourism 2 m temperature difference (ºC) • More accurate forcing for coupled ocean-atmosphere models

Future Work • Case studies using a coupled ocean-atmosphere model -Regional Ocean Modeling System (ROMS) and WRF • Pollen and pollution dispersion within the NJ sea breeze • Use CODAR to determine the offshore extent of the sea breeze Special thanks go out to: Luke Oman, Mike Crowley, Jim Eberwine, Dale Haidvogel, John Wilkin, Hernan Arango, the rest of NWS Mount Holly, and especially ALL of RU COOL Research funded by: National Weather Service’s Cooperative Program for Operational, Meteorology Educatioin, and Training (COMET) References: • Glenn, S. M. , and M. F. Crowley, 1997. Gulf Stream and ring feature analyses forecast model validation, J. Atms. Oc. Tech. , 14, 1366 -1378. • Kwiatkowski, J. , 1999. Observations and analysis of the New Jersey Sea Breeze. M. S. Thesis. Rutgers University. 79 pp. • Song, T. , D. B. Haidvogel, and S. M. Glenn, 2001. Effects of topography variability on the formation of upwelling centers off New Jersey: A simple theoretical model, J. Geophys. Res. , 106, 9223 -9240. http: //marine. rutgers. edu/cool