Download presentation
Presentation is loading. Please wait.
Published byDaniel Morton Modified over 8 years ago
1
Fluxes With input from: USCLIVAR Working Group on High-Latitude Fluxes: Ed Andreas, Cecelia Bitz, Dave Carlson, Ivana Cerovecki, Meghan Cronin, Will Drennan, Chris Fairall, Sarah Gille (co-chair), Ross Hoffman, Gudrun Magnusdotti, Rachel Pinker, Ian Renfrew, Mark Serreze, Kevin Speer, Lynne Talley, Gary Wick Fluxes from Space: Carol Anne Clayson, Sarah Gille, Darren Jackson, Brent Roberts, Joel Scott, Shawn Smith, Gary Wick Ocean Modeling and Reanalysis Comparison: Dmitry Dukhovskoy and Paul Hughes Mark A. Bourassa COAPS & EOAS, Florida State University, bourassa@coaps.fsu.edu
2
Distribution of SHF is Inconsistent Among Products
3
Selected Motivations Differences between flux products are much too large Differences are reduced in modern products (Bourassa et al.) It has been suggested that surface fluxes play a large role in several aspects of Arctic ice melt and growth Links to oceanic deep convection Deep water formation in the Southern Ocean might be influenced by fluxes – particularly latent heat flux (Speer) Indian ocean dynamics very sensitive to surface fluxes Large latent heat flux over water contributes to both the energy and water cycles Observed changes in Hadley and Walker circulation should be associated with changes in surface fluxes SST gradients near western boundary currents estimated to cause monthly averaged regional changes in latent heat flux of >30Wm -2 Surface moisture convergence linked to some clouds?
4
Accuracy Requirements Fluxes are estimated through bulk formulas Goal <5Wm -2 bias in sum of latent and sensible heat flux Goal assessments were done by Chris Fairall Wind spd: 0.4 m/s threshold; 0.2 m/s goal; 0.1 m/s outstanding SST: 0.2 C threshold; 0.1 C goal; ? outstanding Air Temp: 0.2 C threshold; 0.1 C goal; ? Outstanding Spec humidity: 0.6 g/kg threshold; 0.3 g/kg goal; ? Outstanding Goals on random error are not clear, as they are more relevant to short-lived and smaller area forcing For the larger scale applications, sampling will overcome random error. Both of the above statements assume that there is no cross correlation of errors between variables.
5
Comparison of Two Retrieval Techniques Blue – Roberts et al. (SeaFlux) Red – Jackson and Wick Need more data to improve extremes
6
Discussion
7
The period for comparison (for which all products are available) is 03/1992 through 12/2000. Black line is the track from Ryan Maue’s data set Lack of retrieval in areas with too much rain
8
Input to Bulk Fluxes USCLIVAR/SeaFlux 8
9
CCMP NCEPR CFSR 0.004 0.03 0.05 0.08 0.1 0.12 0.15 Greenland ASR Exceedance Probability (U>17 m/s), winter 2005-2007
10
Evaluation of Satellite Retrievals of 10m Ta and Qa Comparison to research vessel observations from SAMOS
11
Progress: Flux Accuracies and Applications 10m 100m 1km 10km 100km 10 3 km 10 4 km 10 5 km 1 hour 1 day 1 week 1 month 1 year 10 years 100 years Leads NWP High Impact Weather Conv. Clouds & Precip 50 Wm -2 10 Wm -2 1 Wm -2 0.1 Wm -2 0.01 Nm -2 5 Wm -2 Polynyas Climate Change Ocean Eddies and Fronts Dense Water Formation Shelf Processes Ice Breakup Atm. Rossby Wave Breaking Upper Ocean Heat Content & NH Hurricane Activity Stress for CO 2 Fluxes Annual Ocean Heat Flux Ice Sheet Evolution Open Ocean Upwelling Annual Ice Mass Budget Unknown Mesoscale and shorter scale physical-biological Interaction
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.