 |
 |
 |
The meteorological observation in Japan issues advisories in the case where there is a possibility of damages due to severe weather like heavy rain and/or strong wind, and issues the warnings in the case where there is a danger of serious damage. JMA has replaced, in the fiscal years 1994 and 1995 the Computer System for Meteorological Services (COSNIETS). For the purpose of strengthening and improvement of meteorological services including provision of information for disaster prevention, such as the advisories and warnings, and for expansion of quantitative expression of the meteorological information, with grade up of this system the "weather distribution forecast and "time sequence forecast" are newly introduced in March 1996. The "weather distribution forecast" provides the forecast of weather, rainfall and temperature up to 24 hours ahead, at 3 hour intervals in 1,500 regions that divides Japan with the mesh size of 20km mesh. The forecast is announced for 11 blocks covering Japan. The "time sequence forecast" is the forecast of sequential weather, rain and temperature. At 3-hour intervals at several places in each prefecture up to 24 hours ahead. It is believed that these forecasts will facilitate measures for disaster prevention or emergency activities in the case of storm, heavy rain, heavy snow, etc. In addition, the Japan Meteorological Agency plans to modernize observation equipment such as weather radars, ground weather observation systems and snow depth gauges. For the purpose of safety landing and taking off of aircraft, the Japan Meteorological Agency engages in meteorological observations at airports and their peripheries at its 85 meteorological offices and the information obtained is provided to the air traffic control organizations and airline companies. At 9 major airports in Japan, the distribution of rain within the radius of 100 km form each airport is observed with the airport meteorological radar. Especially at Kansai International Airport in the fiscal year 1994 and New Tokyo International Airport in the fiscal year 1995, Doppler Meteorological Radars at the Airport were installed to observe the sudden change of wind at low altitudes at the peripheries of the airport (low altitude wind shear) including downburst, which exerts serious effects on the landing or take-off of aircraft. At these airports, the observation of low altitude wind shear will start from the fiscal year 1996 (Fig. 16). In relation to the information on the ocean, the advisory or warning on tidal waves is announced. Analysis of waves, etc. in the Japanese inshore and Northwest Pacific Ocean is conducted and the information is provided to contribute to securing safety of vessels, marine leisure, etc.
(1) Measures at railways Railway corporations practice the regular check
of lines, bridges, aerial lines, etc. in accordance with the regulations regarding
the operation of railways, etc. to grasp accurately and promptly any dangerous
part. Especially in the rainy and typhoon seasons, the check-up is intensified
at seaside, cliffs (Picture. 9),
etc. where there is the fear of the occurrence of landslide and obstruction
to the rails caused by heavy rain and storm. Furthermore, dilapidated structures
such as bridges are replaced or reformed, as the occasion may demand, to prevent
the occurrence of disaster or accident. Of the facilities for the prevention
of disaster, the Japanese government provides the subsidy for the project which
is treated as the same as the public works for the prevention of disaster, such
as the forestry conservation and river improvement. The collapse of embankment
on railways caused by localized torrential downpour exerts grave effects on
the safety operation of trains. For this reason, the Railway Technical Research
Institute has been developing a rainfall disaster inspection and observation
system (RAMIOS) which measures and assesses the danger of collapse of embankments
on railways by rainfall along the railway line (Fig.
17).
(2) Measures at airports When airports are newly established or expanded,
improvement or construction of drainage facilities well harmonized with the
situation of flow of water in the periphery is carried out to secure smooth
drainage of the rain falling on the airport. As a measure against damage caused
by heavy snowfall, equipment with snowplows has been carried out in order to
maintain safety and smooth take-off and landing of aircraft and the manual for
planning and works for snow removal at the run-ways, taxiways and aprons has
been established, which provides details on the standard for decision of initiation
of snow removal and order of the removal works.
(3) Measures at ports The coasts of Japan are exposed to severe natural
conditions such as earthquakes, typhoons, violent waves and winds in winter,
etc. and have often been damaged seriously by tidal waves and tsunami. On the
other hand, as various activities for living and production are centered on
coastal areas of ports and harbors, the high degree of safety is claimed against
the coastal damage. In order to cope properly with any disaster at port and
harbor, the construction or improvement of coastal protection facility for maintenance
coasts have been deliberately carried out. Recently, attention has been paid
to the integrated coast preservation system for protection of the rear area
from damages caused by tidal waves, erosion, etc. by appropriate location of
the coast protection facilities such as banks for the protection of coasts,
beaches, and revetment beaches, and detached breakwater, giving an areal stretch
to those facilities to realize compound functions of these facilities (Fig.
18). This system is not to protect the outer force such as waves only with
banks or revetments but a formula to weaken the force of waves gradually from
the offing to the shore, constituting a tenacious structure to function against
the threat from the sea with solidity. This formula enables an increase in the
durability of facilities and reduction in the crown levels of banks, etc. thus
contributing to gaining a good view of the area and creating a good seashore
space. This will be actively adopted in the future.
|
|
|