The Japan Meteorological Agency (JMA), which is an external organ of MOT, is responsible as the National Meteorological Service in Japan or contributing to the improvement of public welfare including prevention and mitigation of natural disasters, safety of transportation, prosperity of industries, and international cooperation activities. The major services are to issue weather forecasts in short-range, one-week, and long-range; warnings/advisories against typhoon and heavy rainfall/snowfall; warning/forecast against tsunami, storm surge, ocean waves and flood; and to provide information on earthquake and volcanic activities.
In order to ensure these services, JMA is continuously improving its systems of observations, national/international telecommunications and weather analysis/forecasting. Recently, more accurate and precise meteorological information has become available as a result of the system improvements: The meteorological observing system including the Geostationary Meteorological Satellite (GMS), the Automated Meteorological Data Acquisition System (AMeDAS), and the associated telecommunication network have been upgraded, a high-speed super computer data processing system have been introduced; and numerical weather prediction models have been sophisticated.
Recently human being is facing global environmental issues, in particular the global warming due to increasing in concentrations of greenhouse gases in the atmosphere. JMA is operationally making observations and monitoring of atmospheric ozone and greenhouse gases.
Also, JMA is modernizing the seismological observation to support the earthquake prediction system for coming Tokai Earthquake in joint cooperation with other governmental agencies, research institutes and universities. Since 1987, the computerized Earthquake Phenomena Observation System (EPOS) has been in operation to monitor and identify precursory anomalies of crustal movement and to support the tsunami warning service.
Since more diversified meteorological information is increasingly required in the development of our socio-economic system, JMA has been making every effort to meet these social needs in improving the long-range forecasting and now casting, in facilitating the climate-related activities, and in consolidating the tsunami warning and earthquake prediction system.
2 Information services of Meteorological and Oceanographic Phenomena
JMA provides weather forecasts for each day and the following two-days; one-week weather forecasts; long-range forecasts; advisories, forecasts and warnings of specific meteorological and oceanographic phenomena; aeronautical forecasts and warnings in case of typhoons or torrential rain, and provides specific meteorological information for industries such as railways, electric power generation, agriculture and forestry, and fisheries.
Of these forecasts, advisories and warnings which greatly affect the nation's daily life are widely distributed to the general public through radio, television, newspapers and the dial-177 telephone service.
3 Observations of Meteorological and Oceanographic Phenomena
Observations of meteorological and oceanographic elements such as atmospheric pressure, temperature, humidity, wind direction and speed, precipitation, sunshine duration, weather, sea water temperature and ocean currents are the basis of the meteorological services. JMA conducts three-dimensional composite observations: surface observations made at observatories and at AMeDAS sites; meteorological satellite observations; meteorological rocket observations; rawinsonde observations; weather radar observations; plus oceanographic and marine meteorological observations with ships and ocean data buoys.
(1)Meteorological Observations from Space
GMS is stationed above the equator at 1400E, and observes about 1/4 of the Earth's surface with a Visible and Infrared Spin Scan Radiometer (VISSR). It provides us with information on
