Altimetry and Biogeochemistry

Adrian Martin

With input from

John Allen,Graham Quartly,Meric Srokosz,AndrewYool

Altimetry and Biogeochemistry

• Biomes: the big picture• 3 examples:

- Silica cycle- Filaments- Biodiversity

•The role of altimetry•Why wide swath is good news

Sarmiento et al., GBC, VOL. 18, GB3003, doi:10.1029/2003GB002134, 2004

Biomes

Biomes

Need multidisciplinary local studies tocharacterise each biome.

Such detailed studies crucial to understand how functioning of biomeresponds to different forcing.

Phytoplankton & biogeochemistry

diatoms

coccolithophores

Silica cycle

FISHES Cruise, 2001

Allen, J.T. et al. (2005)Nature, 437, 728-732.

Filaments

Cruise D321August 2007

SSH

SST

Filaments

-20-22

60

59

Filaments

Filaments

Biodiversity

BiodiversityPicophytoplankton Heterotrophs Synechococcus

Large phytoplankton Bacteria Viruses

Central problem

How do we extrapolate knowledge of processes at a local scale toquantitative estimates at the biome scale?

The role of altimetry

Altimetry offers information crucial to extrapolating to the biome scale.

Specifically it offers:- a physical context- dynamical information- a means of tracking features- a means of auditing features- data even when there is cloud

So why is wide-swath so much better?

Better resolution of currents

Higher resolution of features

Less gaps for features to ‘fall into’

Potential for quantifying vertical fluxes

5) What other remote measurements would complement the altimetric data? HR wind, SST, colour, pigments, SSS 6) What other chemical & biological properties of seawater would it be useful to measure together with SSH?Depends on the question…

Workshop questions

O(100km) swath width- to cover a process cruise area- large enough to accommodate

scale of local mesoscale features

Re-visit every 5 days

Ability to resolve 10km features (20km wavelength)

What specification for biogeochemistry?