http://www.oifii.org/ns-org/nsd/ar/sp/

ratio/html_m

Stephane Poirier

Relation between AR-SP library code http://www.oifii.org/ns-org/nsd/ar/sp/ratio/html_m

/ and Arnaud Mialon's chapter 2 figures (snowcover extent detection from SSM/I

brightness temps.)

Next-phase Goal

AR-SP ratio library source code is a generalization from AR-AM ratio library

AR-SP code is to be applied on both SMMR and SSM/I periods NSIDC's TBs.

AR-AM code was designed and validated mostly to the SSM/I periods NSIDC's TBs.

Currently uncertain if snow-free season is well localized in time when ratio library used with SMMR period TBs.

Current Wishes

Historically, only 2 seasons can be easily identified. A season where snow is present versus a season without any snow.

Currently uncertain if summer start day (or winter end) and summer end day (or winter start) are well identified when ratio library used with SMMR period TBs.

This presentation attempts to link the AR-SP ratio library source code lines implementing AR-AM ratio algorithms key concepts in order to validate and possibly improve the generalization.

http://www.oifii.org/ns-org/nsd/ar/sp/ratio/html_m/etape_ratio.html

Following step 1, 2, 3 and 4 is step 5 where function calcul_moyecart() is called

[moy_ete,ecart_ete,moy_hiver,ecart_hiver,seuil]=calcul_moyecart(zone,dataset,phase,pol,an,pathratio);

The function calcul_moyecart() computes averages and standard deviations for both snowfree and snowcovered periods as well as a threshold

calcul_moyecart() can also be found at link http://www.oifii.org/ns-org/nsd/ar/sp/ratio/html/calcul_moyecart.html(with line numbers and URLs for other matlab function names)

For both SMMR and SSM/I periods, the threshold is set using the line seuil=moy_ete-2.*ecart_ete; (line numbers 158, 253, 300 and 379 )

http://www.oifii.org/ns-org/nsd/ar/sp/ratio/html_m/calcul_moyecart.html

Cost Analysis

Indicate the financial advantages for the customer

Compare quality and price with those of the competition

Strengths and Advantages

Summarize the special features and advantages of the product being introduced

Next Steps of Action

Explain the steps that now need to be taken