Gulf of Maine Alexandrium fundyense Model Results – 2011

 

Ruoying He1, Yizhen Li1, Dennis McGillicuddy2, Don Anderson2, Bruce Keafer2

1North Carolina State University

2Woods Hole Oceanographic Institution

 

 

Disclaimer: these simulations are for experimental purposes only.

 

Results here represent model solutions initiated from a cyst abundance map from October 2010, with germination, growth, and transport of Alexandrium fundyense cells driven by the factors listed below.

 

Physical circulation model

Multiple nested ROMS, ca. ~1km resolution in GOM

Tides (M2, S2, N2, K2, K1, O1, Q1)

6-hourly wind and heat fluxes from NOAA/NCEP NOMADS (35-km resolution)

River runoff data from USGS

Sea surface temperature from satellites

Initial conditions and open boundary conditions from large-scale parent model (HYCOM)

 

Alexandrium fundyense model

Population dynamics from Stock et al. (2005); McGillicuddy et al. (2005), He et al., (2008) and Li et al.(2009)

Cyst maps from Fall 2010 Survey in comparison with earlier years

(http://omglnx3.meas.ncsu.edu/yli/cystmap/cystmap_04_10.png)

Solar radiation from NOAA/NCEP

Monthly climatological nutrient fields from University of Maine

The mortality rate of A. fundyense is now parameterized using the temperature dependent Q10 formulation (Durbin and Durbin, 1992)

 

Modeled A. fundyense bloom

          An animation showing surface wind fields and modeled bloom conditions from February 1, 2011 to July 17, 12:00, 2011

http://omglnx3.meas.ncsu.edu/GOMTOX/2011forecast/dino_11.htm
 
An 3-D animation showing modeled surface and subsurface cell abundance from February 1, 2011 to July 17, 12:00, 2011
           http://omglnx3.meas.ncsu.edu/GOMTOX/2011forecast_3d/dino_11.htm

Caveat

         Accuracy of the forecast may be affected by changing water mass characteristics in the Gulf of Maine, which in turn can have a direct effect on the growing conditions for Alexandrium.
         For example, in 2010 near-surface coastal waters were warmer, fresher, and lower in nutrients than usual (McGillicuddy et al., in preparation).
         The GOMTOX team believes this suppressed what otherwise would have been a major regional bloom, which had in fact been forecast for that year.
         Recent observations from NOAA’s Ecosystem Monitoring Program (EcoMon) surveys and Fisheries and Oceans Canada's Atlantic Zone Monitoring Program (AZMP)
         indicate that similar water mass anomalies may occur in 2011, suggesting the bloom could be suppressed this year as it was in 2010.

Model-data comparisons

 



Figure 1. Comparison between Observed (left) and modeled (right) surface cell concentration (unit: Cell#/L) on  April 7th, 2011. (Thanks to MWRA for providing preliminary observations)




Figure 2. Comparison between Observed (left) and modeled (right) surface cell concentration (unit: Cell#/L) on  May 20th, 2011. (Thanks to MWRA for providing preliminary observations)







Figure 3. Comparison between Observed (left) and modeled (right) surface cell concentration (unit: Cell#/L) on  May 25th, 2011. (Thanks to MWRA for providing preliminary observations)





Figure 4. Comparison between Observed (left) and modeled (right) surface cell concentration (unit: Cell#/L) on  June 1st, 2011. (Thanks to MWRA for providing preliminary observations)




Figure 5. Comparison between Observed (left) and modeled (right) surface cell concentration (unit: Cell#/L) on  June 8th, 2011. (Thanks to MWRA for providing preliminary observations)



Figure 6. Comparison between Observed (left) and modeled (right) surface cell concentration (unit: Cell#/L) on  June 16th, 2011. (Thanks to MWRA for providing preliminary observations)



Last update: July 16, 2011