1. SW – 5 PRIMARY PRODUCTION IN THE OCEAN Francisco Chavez, Miquel Rosell, Anna Rumyantseva, Joanna Paczkowska, Cristina Garcia – Munoz, SM Sharifuzaman

2. Rationale (from http://modis.gsfc.nasa.gov) Factors affecting phytoplankton growth: Physical controls (turbulent mixing and light exposure) Biological controls (grazing and respiration) Chemical controls (availability of nutrients) Our goal: Develop a growth index based on temperature, nutrients and light to describe patterns of global primary production distribution.

3. Methods GROWTH INDEX Temperature index: Light index Nutrient index: Input Data: 1º monthly climatology -Chl a (SeaWIFs) -PAR (SeaWIFs) -Surface Nitrate concentration (WOA) Annual average -MLD (model output) -SST (blended satellite products) -Nutricline (WOA)

4. Methods Temperature Index: Nutrient Index: Irradiance Index: PAR/MLD GI = T 0.8 x N x I All the index were normalized by the maximum values to obtain a value between 0 and 1 (from Behrenfeld & Falkowski, 1997) If [Nitrate] = 0 then 0.1 If [Nitrate] >= 2 then 1 Otherwise [Nitrate]/nutricline

5. Growth Index performance Nutrient Index Temperature Index PAR Index

6. Growth Index performance

8. Conclusions The growth index seems to correlate between with chlorophyll in low/mid latitudes Lack of data in high latitudes could lead to some biases in our analysis for this region FUTURE WORK: - Improve performance in the Growth Index - Introduce limiting factors, mainly IRON -> Dust - Compare coastal and ocean areas

9. Thank you for your attention