Q: When the sky is hazy, does that mean that DSS is occurring?
Q: Is today's DSS heavy or light?
Q: Is it true that some DSS may pass through the air over Japan?
Q: Is there any problem to hang my laundry out to dry tomorrow?
Q: Where did the DSS over Japan today originate from?
QWhen the sky is hazy, does that mean that DSS is occurring?
AEven when the sky is hazy it does not necessarily mean that DSS is occurring. The sky is sometimes hazy due to particulate matter originating from atmospheric pollution. Since LIDAR can distinguish between DSS and atmospheric pollutant particles, which is difficult to do visually, please refer to the information on this Real-time DSS Information website. The visibility near the ground may be poor sometimes due to sand and dust flying locally.
QIs the DSS today heavy or light?
AThe heights of the cylinders displayed on this Information page correspond to the amount of DSS floating near the ground (up to 1 km above ground). (Note: On cloudy days, the height represents the amount of DSS up to the height of the clouds.) As a result, by comparing the real-time screens with the past DSS events, it is possible to compare whether the current DSS is heavier or lighter than the past DSS. In Japan, DSS rarely exceeds 0.3 mg/m3 when converted to concentration, but if DSS exceeding 0.3 mg/m3 occurs near the ground, it may cause visible dirt on laundry and cars.
For the amount of DSS near the ground, the concentration of suspended particulate matter (SPM) also serves as a reference. On the page for SPM data, i.e. "Soramamekun" (Japanese text only) , select the region that you want to view and the display item "Suspended Particulate Matter". When there is DSS event and the SPM concentration is higher than the range displayed in yellow, it can be determined that there is a heavy DSS.
In addition, in this page, when the provisional data (hourly figure) for the SPM observation data at the ambient air pollution monitoring station closest to the LIDAR location exceeds 0.2 mg/m3 and, moreover, the DSS near the ground is heavy (exceeding 0.3 mg/m3) based on LIDAR, the character is displayed on the cylinder.
QIs it true that some DSS may pass through the air over Japan?
AWhen you click on a cylinder on the map, an enlarged cylinder is displayed, and it is possible to see the area around which the DSS passed over as well as the extent of the DSS, up to 6 km above ground. When only the top part of the enlarged cylinder is red, the DSS is judged not to be occurring on the ground, but simply passing through the air.
QIs it safe to hang my laundry out to dry tomorrow?
ASince the Japan Meteorological Agency forecasts DSS for the following day, please look at the Japan Meteorological Agency's announcement on their "Aeolian Dust Information page". On the CFORS page, which is provided by the National Institute for Environmental Studies and Kyushu University as part of their joint research using LIDAR data, simulation results for up to the day after next are available for reference.
QWhere did the DSS over Japan today originate from?
ADSS originates from source areas such as the Takla Makan Desert, Gobi Desert, and Ocher Plateau in inland China to Japan through various transport processes. It is possible to retroactively view the paths of DSS from its source area to Japan in the past by using animated DSS distribution diagrams based on model calculations on the CFORS page. Please use the CFORS page as a reference.
Questions and Comments
If you have any questions or comments regarding this website, please contact the Air Environment Division, Environmental Management Bureau, Ministry of the Environment at KOUSA01@env.go.jp
Copyrights of materials, data, etc. listed on this website are owned by the respective agencies at which LIDAR systems are installed, as well as the National Institute for Environmental Studies.