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Impacts of Climate on Arctic Pacific Environment

This study investigates the changes in primary production and chemistry of the Arctic Pacific environment due to climate change. The research focuses on the impact of climate change on the biogeochemistry and ecology of the Chukchi and Beaufort seas.

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Impacts of Climate on Arctic Pacific Environment

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  1. Impacts of Climate on EcoSystems and Chemistry of the Arctic Pacific Environment (ICESCAPE)Kevin R. ArrigoStanford University

  2. Background

  3. Given ongoing changes in the Arctic Ocean…How has primary production changed in recent years?

  4. Changes in Arctic Productivity • Between 1998 and 2009, annual primary production increased by 134 Tg C(statistically significant trend) • A 38% increase over the last twelve years • Unexpected given • presumed nutrient • limitation • Largest increases • on continental • shelf

  5. Changes in Arctic Productivity Annual production highly correlated to open water area

  6. Changes in Arctic Productivity Increase in production also related to increase in open water season Open water season has lengthened by an average of 3.8 days yr-1 over last 12 years 45 days longer in 2009 than in 1998 Length of Open Water Season Days open water >5 x 106 km2

  7. Annual Primary Productivity (1998-2009) Tg C yr-1 27 • Regional variability • Atlantic sectors most productive • >50% of Arctic primary production • Low sea ice cover 26 23 40 29 50 109 123

  8. Percent yr-1 Change in Primary Productivity 1998-2009 Largest annual increase: East Siberian Sea Smallest: Greenland Sea Significant values in white 4.4 10 3.8 4.8 0.2 4.7 2.3 -0.3

  9. Changes in Arctic Productivity • What is responsible for this increase? • Lower ice cover and longer growing seasons play a role • Increased nutrient supply also must be important - Greater shelf-break upwelling as sea ice retreats? - Increased eddy activity? - Intensified advection of nutrients from Bering Strait?

  10. ICESCAPE • Central science question: • What is the impact of climate change (natural and anthropogenic) on the biogeochemistry and ecology of the Chukchi and Beaufort seas?

  11. ICESCAPE

  12. ICESCAPE

  13. ICESCAPE

  14. ICESCAPE

  15. ICESCAPE

  16. ICESCAPE • When? • June 15 - July 21, 2010 • & September 2011 • Where? • Start in Dutch Harbor, AK • Cruise to Bering Strait • Beaufort/Chukchi Sea • - Continental shelf • - Canada Basin • Sea ice sampling • Back through Bering Strait • End In Seward, AK

  17. ICESCAPE Physical Oceanography: Bob Pickart – XBTs, ADCP, eddies Jim Swift – CTD, O2, salinity Mike Steele – ARGO floats Jinlun Zhang – 3D coupled physical-chemical-biological ice-ocean modeling

  18. Eddy formation from dense water outflow Pickart/Arrigo 2-D transect through a cold-core eddy in 2002 Mid-depth, cold-core eddy We hope to conduct a three-dimensional survey of a cold-core eddy, with the full suite of biological measurements.

  19. ICESCAPE Biological Oceanography: Kevin Arrigo and Greg Mitchell – Primary production, microalgal abundance (ice and water column) and physiology Sam Laney – Phytoplankton community composition Eva Ortega-Retuerta - Bacterial production Jinlun Zhang – 3D coupled physical-chemical-biological ice-ocean modeling

  20. Monitoring Climate-Driven Changes in Arctic Algal Assemblages PIs: Sam Laney & Heidi Sosik Biology Dept., Woods Hole Oceanographic Institution Use Imaging FlowCytobot technology to assess spatial & vertical variability in Arctic algal assemblages. Combines flow cytometry, individual cell imaging, & automated image classification to assess the composition of microalgal assemblages. Quantifies cells ml-1 of different algal taxa Instrument images ~500 cells per mL in ~ 4 mins. Uses a computer & classifier algorithm to sort images by “taxon” Chaetoceros Ceratium Cylindrotheca & ~25 other categories currently… Olson et al. 2003; Olson & Sosik 2007; Sosik & Olson 2007

  21. ICESCAPE Chemical Oceanography: Nick Bates – Carbon cycle measurements (e.g. DIC, alkalinity) Jim Swift – Nutrients (e.g. NO3, NO2, NH4, PO4 , SiO3), O2, salinity Jinlun Zhang – 3D coupled physical-chemical-biological ice-ocean modeling

  22. STS/ODF will collect water samples from a 12-place rosette with 30-liter bottles. Rosette will be outfitted with: - SeaBird 911+ CTD w/ dual C/T sensor - Oxygen sensor, - Flourometer - Tranmissometer - CDOM fluorometer On-board seawater analysis equipment will include: - Salinometers - Oxygen autotitration rig - 5-channel nutrient autoanalyzer (NO3, NO2, NH4, PO4, and SiO3).

  23. ICESCAPE Optical Oceanography: Stan Hookerand Greg Mitchell – Spectral Lu, Ed, AOPs, IOPs Rick Reynolds and Dariusz Stramski – Particle size distribution, bb, volume scattering, SPM Atsushi Matsuoka – aCDOM Robert Frouin – Atmospheric correction algorithm

  24. Mitchell Group Chl a (mg m-3) Southern Ocean High latitudes are unique Make detailed measurements of ap, ad, CDOM and backscatter to better understand Arctic Ocean bio-optical properties to Improve Chl a and productivity algorithms required for ecological modeling. In polar regions, standard NASA algorithms based on low latitude data underestimate Chl a (Mitchell 1992, Arrigo et al. 1998). Will collect data to determine relationships between reflectance, Chl a and IOPs.

  25. A B C bbp4400000 aph440 adg440 Mitchell Group Inversion of the bio-optical properties in Mackenzie Bay, Beaufort Sea using MODIS-Aqua data of 7/6/2008 and QAAv5 algorithm of Lee et al. A. aph = phytoplankton absorption B. adg = CDOM + detritus C. bbp = particle backscatter. Will determine details of absorption and backscattering to improve algorithms and retrievals for key biogeochemical properties Will provide near-real time delivery of satellite imagery to the ship for cruise planning.

  26. Improving Existing Satellite Color Observations of the Chukchi and Beaufort Seas for Biogeochemical Modeling PI: Robert Frouin, SIO/UCSD; Co-I: P.-Y. Deschamps, LOA/U. Lille; Co-I: B. Pelletier, I3M/U. Montpellier Theme Improved atmospheric correction of satellite ocean-color imagery in the presence of snow/ice and clouds. Objective Generate, for the Chukchi and Beaufort seas, a daily time series of satellite-derived marine reflectance and chlorophyll concentration at 4.63 km resolution. Approach - Use of multiple ocean-color sensors (MERIS, SeaWiFS, MODIS). - Use of appropriate atmospheric correction algorithm (POLYMER). - Reconstruction of missing data.

  27. MERIS image of the Chukchi Sea showing that water reflectance is correctly retrieved by the POLYMER algorithm, but not by the MEGS algorithm in the presence of a large semi-transparent cloud.

  28. ICESCAPE Sea Ice: Don Perovich – Concentration, thickness, salinity, snow cover, optical properties Kevin Arrigo – Primary production, microalgal abundance, and physiology Karen Frey – CDOM, DOC, O2 isotopes Jinlun Zhang – 3D coupled physical-chemical-biological ice-ocean modeling

  29. Planktonic Ecosystem Response to Changing Sea Ice and Upper Ocean Physics in the Chukchi and Beaufort Seas: Modeling, Satellite and In Situ Observations Jinlun Zhang, Carin Ashjian, Robert Campbell, Victoria Hill, Yvette Spitz, and Mike Steele Biology/Ice/Ocean Modeling and Assimilation System (BIOMAS)Synthesis and modeling of the integrated system of sea ice, the upper ocean, and the plankton ecosystem in the Chukchi and Beaufort seas

  30. BIOMAS grid configurationand ecosystem model

  31. ICESCAPE • Data Policy: • Preliminary data will be staged at an ftp site at Stanford • http://ocean.stanford.edu/ICECAPS • All data collected will be subject to the standard NASA Earth Science data policy (http://nasascience.nasa.gov/earth-science/earth-science-data-centers/data-and-information-policy/). • Data collected are required to be submitted to the NASA SeaBASS archive (http://seabass.gsfc.nasa.gov/) within one year of collection.

  32. ICESCAPEThank You

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