Volcanic as and dust monitoring with geostationary satellites / Surface wind estimation using rapid-scan AMV's.

Here are the replies to the questions posed by the audience during the JMA presentations.
Courtesy of Kurihara-san and Hayashi-san

Question 1: could you please give some more details about how JMA determine the height of volcanic ash clouds from the satellite imagery ?

Answer: I attached an pdf (MSC_VA_DETECTION_HEIGHT.pdf) for some pieces of information on ash detection and height assignment to the appropriate position on the timetable at http://www.virtuallab.bom.gov.au/events/science-week/subjectsandcomments/ . Please note that these algorithms are still tentative. As for the details on the H2O-intercept, please refer to the paper 'Nieman et al, 1993: A Comparison of Several Techniques to Assign Heights to Cloud Tracers'

Question 2: please explain the four illustrations in the movie "2shinmoe"

Answer: Images are RGB composite (left of the top), mass loading (right of the top), ash cloud height (left of the bottom) and particle size (right of the bottom) (please see the attached 'Shinmoe2.jpg').

Question 3: Are there any rapid scan AMV products on the JMA website that we could look at ?

Answer: Unfortunately, rapid scan AMV products is not operational phase but development phase now. So, the rapid scan AMVs are not available on our website.

Question 4: over what domain (range of latitude and longitude) does the MTSAT satellite perform the rapid scan operation ?.

Answer: Please see the attached (range_of_rapid_scan.jpg).

Question 5: do you perform continual rapid scanning of AMV over Japan, or do you only do this if there is a Typhoon or other serious weather event threatening your island ?.

Answer: Currently, We produce rapid scan AMV in quasi-operational base. We compute rapid scan AMVs continuously (quasi-realtime), but this is only for investigation.