MODIS Snow Cover Product Usage (as of 4/24/01) Total number of requests to date: 144 Unique users: 51 Total amount of data distributed: 62.2 Gb MODIS Snow Cover Product Requests by Data Type (from EDGRS) Intro: Name, UsrSvc Rep, primary POC for MODIS user questions and monitoring requests Release of Snow: Oct. 13, 2000 25 April 2001 PoDAG XVIII

MODIS User Feedback Input from 6 users who have submitted at least one order for MODIS snow cover data. ~10% of unique users. Represent government, research, and commercial entities. 25 April 2001 PoDAG XVIII

What was the application of the data? Validate gridded snow cover product with NCDC ground data. Estimate snow cover for Canada for climate research. Compare similar channels of MODIS/AVHRR for snow detection and cloud detection algorithms. Software development – ensure data can be imported. Test order to see if ordering MODIS data as easy as obtaining ASTER data. 25 April 2001 PoDAG XVIII

Has the data met your need? Is it useful? Yes! Further evaluation needed. High number of channels a plus. Used pre-release data in validation effort. Data contained known problems. For those using the data. One of users not actually using MODIS data. Further eval. = inline with MODIS ST stance that products are “provisional” maturity level 25 April 2001 PoDAG XVIII

What was your experience with the EOS Data Gateway (EDG)? Difficult to navigate at first, but easy once the set up is learned. User profile is handy for saving most recent search criteria. Convenient for single scenes. Too slow for high number of scenes. Direct access to ftp site or dbase would be more convenient. Did it take you long to place the order? Had you used it before? Did it take you long to understand the system? Did you experience any problems? # of scenes: turnaround time biggest factor 25 April 2001 PoDAG XVIII

What was your experience with visualizing and working with the data? Steep learning curve, especially if first in group to use it. “HDF is gross to look at” and data producers do many different things within the format. Easy to work with since tools are available. ISIN grid difficult at first, but handled okay by ENVI software. Any issues with accessing the data in HDF-EOS format? Learning curve for HDF-EOS? Did you use the QA data? Were you able to access the metadata in the file? Did you use the metadata? Any issues with geolocation? Answers varied depending on experience with and exposure to HDF-EOS. QA data not used much—tools not available to read it. 25 April 2001 PoDAG XVIII

How would you rate the service of the NSIDC DAAC in support of MODIS data? Needs have been well met. Documentation and web resources at NSIDC used extensively. Has not required support. Figured out problems from colleagues or from online resources. Found the HDF site (NCSA) and MODLAND browse site helpful. 25 April 2001 PoDAG XVIII

What is your overall sense of the products What is your overall sense of the products? How would you rate them and why? Quality of data good. Sometimes can not get to data due to system being down. Such is life—no real complaints. Lag between real time and availability of processed data is a drawback. In some settings, MODIS is a significant improvement over existing data sets. In other areas, there is no change. Benefit of existing products over MODIS is the easier access and that they can be accessed in near real-time. Good, but people need to be able to easily find what they are looking for and there are not many packages helpful for data in HDF. Users seem to understand data volumes involved and that direct access to ftp site or database is not feasible. Users understand that the system down times are part of reality. 25 April 2001 PoDAG XVIII