New Analytical Methods

N2 fixation

  • Cassar, N., Tang, W., Gabathuler, H., Huang, K. 2018. Method for high frequency underway N2 fixation measurements: Flow-through incubation Acetylene Reduction Assays by Cavity ring down laser Absorption Spectroscopy (FARACAS). Analytical Chemistry, DOI: 10.1021/acs.analchem.7b04977.
    • US Patent Application # 62/619,303
  • Cassar, N., Bellenger, J.-P., Jackson, R. B., Karr, J., Barnett, B. A. 2012. N2 fixation in real-time by cavity ring-down laser absorption spectroscopy.  Oecologia: doi:10.1007/s00442-011-2105-y.

Biological O2 and pCO2

  • Cassar et al. A second generation equilibrator inlet mass spectrometer. In prep. (EIMS nXT Instruction Manual)
  • Cassar, N., Barnett, B. A., Bender, M. L., Kaiser, J., Hamme, R. C., Tilbrook, B. 2009. Continuous high-frequency dissolved O2/Ar measurements by Equilibrator Inlet Mass Spectrometry (EIMS). Analytical Chemistry 81(5): 1855-1864.

Dissolved Inorganic Carbon (DIC)

Carbon Stable & Radio-Isotope Disequilibrium & Fractionation

  • Cassar, N., Laws, E. A., Popp, B. N., Bidigare, R. R. 2002. Isotope disequilibrium Experiments: Sources of inorganic carbon for photosynthesis in a strain of Phaeodactylum tricornutum. Limnology and Oceanography 47: 1192-1197.

Matlab Scripts & Functions

Satellite algorithms

Satellite NCP algorithms

Global Ocean

Genetic Programming NCP (Li & Cassar 2016)

This section provides access to our oceanic satellite NCP estimates for the world’s oceans based on genetic programming and support vector machine.  These products are based on:

  • Sensor: SeaWiFS and MODISA
  • Spatial resolution: 4 and 9 km
  • Temporal resolution: daily, 8-day, monthly and climatology
  • NCP_metadata.

Further description of the algorithms is provided in:

Li, Z. & Cassar, N. 2016. Satellite estimates of net community production based on O2/Ar observations and comparison to other estimates. Global Biogeochemical Cycles, doi: 10.1002/2015GB005314.

Data access methods

Access estimates based on specific algorithms:

Southern Ocean

This section provides access to our oceanic satellite NCP estimates for the Southern Ocean based on self-organizing maps/artificial neural networks.

Further description of the algorithms is provided in:

Chang, C.-H., Johnson, N. C., Cassar, N. 2014. Neural network-based estimates of Southern Ocean net community production from in-situ O2/Ar and satellite observations: A methodological study. Biogeosciences, 11: 3279-3297.

Data access method: Access Southern Ocean NCP estimates here: Chang et al. (2014) : Southern Ocean SOM NCP

Western Antarctic Peninsula

This section provides access to our oceanic satellite NCP estimates for the Western Antarctic Peninsula based on a Bayesian hierarchical model.

  • Antarctic Peninsula NCP_metadata

Further description of the algorithms is provided in:

Li, Z., Cassar, N., Huang, K.,  Ducklow, H., Schofield, O. 2016. Interannual variability in net community production at the Western Antarctic Peninsula region (1997-2014). Journal of Geophysical Research, doi: 10.1002/2015JC011378.

Data access method: Access WAP NCP estimates here:  SeaWiFS and MODISA

Satellite N2 fixation algorithms

This section provides access to our oceanic satellite N2 fixation estimates for the world’s oceans based on random forest and support vector machine.

Further description of the algorithms is provided in:

Tang, W., Li, Z., Cassar, N. Machine learning estimates of global oceanic nitrogen fixation. Submitted.

Data access methods

Access estimates based on specific algorithms:

  • Tang et al. (2019) (RF)
  • Tang et al. (2019) (SVR)

Data Products

    1. O2/Ar-NCP observations

    2. N2 fixation estimates (in prep.)

    3. High-resolution DIC estimates

    4. Link to sequencing reads (in prep.)

Family recipes

ZE KIF (a collection of family [and others’] recipes)

“Cette cuisine est un monde dont la cheminée est le soleil.”      V. Hugo