Technological advances have ensured that maritime, aviation and land transport systems are generally robust in the face of extreme weather events. However, when infrastructure failures occur they have a severe impact on the dependent communities and their industries.
The potentially devastating impacts of winds, waves, sea ice and storm surges on all aspects of marine operations dominate the design and operation of ships, port facilities and coastal hydraulics. The design considerations range from ensuring the sea-worthiness of vessels to withstand defined sea states, through offshore platforms that can with stand, for example, the one-in-one hundred year storm for a given location, to building sea defences and harbour installations to cope with similarly rare storm surges. All these activities require the extensive use of climatic data collected over many decades.
Road and railway structures are built to make traffic more efficient and to minimize disruptions from rain and flooding. Many meteorological hazards have been ‘engineered out’ of land transport systems, as high bridges have been built to avoid potential flooding from rain swollen rivers and tunnelling has avoided disruption from snow accumulation and avalanches on high mountain passes. The decision to make these infrastructure investments all use historical climate data. The economic viability of the massive investment hangs on continuity of operations, so disruption of the transport system due to weather incurs a large economic cost. Even in the most arid regions, the land route must be carefully surveyed and the climatology assessed to design against occasional flooding of crossings over generally dry riverbeds.
In the development of new airports, and even the expansion of existing ones, siting and design must take into consideration the meteorological factors that could disrupt operations and therefore add to the overall cost of operations. Fog, low clouds, snowfall, locally strong winds and poor visibility are a few of the important weather-related events.
The Hong Kong International Airport opened in 1998, provides a case study for the design of airports. Meteorological analyses related to planning and design of the airport site began in the late 1970s. These included wind shear and turbulence investigations necessitated by the hilly terrain near the site. Measurements of the prevailing easterly winds helped in deciding the alignment of the runways. Other climate information, including cloud base and visibility, contributed towards determining the projected runway usability as part of the economic evaluation. One finding from the analysis of the data gathered is that, over the past few decades, there has been a trend towards reduced visibility. Operational efficiency of the airport could be reduced in future if the trend continues.
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