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 Ocean Observation Lab NJ SOS Meteorological Forecast Component

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

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

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 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. 18:30 UTC 20:35 UTC 22:30 UTC 00:25 UTC

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. Can affect almost all of New Jersey and into SE Pennsylvania. Focus for occasional severe thunderstorm development. Sea Breeze Delaware Bay Breeze

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. Can affect almost all of New Jersey and into SE Pennsylvania. Focus for occasional severe thunderstorm development. Forecast problem: Tourism and Energy 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

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

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

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

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

Regional Atmospheric Modeling System Case Studies Model Specifications Three nested grids Grid 1 – 32 km resolution 34x34 points with 40 s time step Grid 2 – 8 km resolution 50x50 points with 13 s time step Grid 3 – 2 km resolution 90x106 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 Study area in red

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

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

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 5th – July 27th July 5th SSTs July 27th SSTs

Upwelling vs. Non-Upwelling SST July 5, 2000 2 m Temp (ºC)/Upwelling SST 2 m Temp (ºC)/Non-Upwelling SST 2 m Temp (ºC) Sea Breeze front 5 – 10 km farther inland during upwelling SST (upper left) 2300 UTC 2300 UTC 2300 UTC 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 More accurate forcing for coupled ocean-atmosphere models 2 m temperature difference (ºC)

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 for 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