Biological Models NPZD & CPD Rubao Ji Collaborators: Davis, Chen, Beardsley, Townsend, Durbin, Runge, Flagg, Tian, Qiao, Petrik

Status On-line coupling (off-line in future?) Initiated NPZD with climatology (NP) Completed 1995 whole year run for NPZD Gathered copepod data (GLOBEC,MARMAP, ECOMON, AZMP) Testing CPD model (Pseudocalanus), impletmented “stage with mean age” method, testing “EOF” method Ready for NPZD run in other GLOBEC yrs

Model structure

Surface - Nitrogen

Surface - Phytoplankton

Transect - Nitrogen

Transect - Phytoplankton

Model-data comparison (1) Chl-a on the crest of GB (< 60m) in 1995. Data from E. Durbin

Model-data comparison (2) Chl-a on NEP and SF in 1995. Data from E. Durbin

Nitrogen cycle Redline from Pastsuzak et al., 1982

CPD Initial Condition

Day 30 E N C A

Day 90

NAO Slope Water NAO- Labrador Slope Water Intrusion Colder, Fresher Less Nutrient NAO+ Warm Slope Water Intrusion Warmer, More saline and Nutrient rich Drinkwater et al., 2003

Nitrogen Initial Condition Climatological Condition (CC) Bottom Enriched Condition (BEC)

CC VS BEC on GB CC BEC

Flux comparison CC BEC

CC VS BEC in JB CC BEC

CC VS BEC in WB CC BEC