Extreme weather

Climate change is likely to substantially affect human health by changing the magnitude and frequency of extreme weather events (88). Climate change projections are based on the anticipation of increasing means or norms. Global or regional climate models are not well able to forecast future climate variability, whether daily, interannual or interdecadal. Changes in extreme events are forecast by estimating changes in probability distributions.

The effects of natural disasters are increasing, both in Europe and globally (Table 2). An analysis by a reinsurance company (91) found a three-fold increase in the number of natural catastrophes in the previous 10 years compared with the 1960s. This trend primarily results from global trends, which affect population vulnerability rather than changes in the frequency of extreme events. The reasons for the observed increase in the effects of disasters in Europe are:

• increasing concentrations of people and property in urban areas;

• settlement in exposed or high-risk areas such as flood plains and coastal zones; and

• changes in environmental conditions, such as deforestation increasing the risk of flooding.

Several assessments for Europe have concluded that the risk of river flooding will increase. The hydrological cycle will be more intense in a warmer climate. This will entail more episodes of heavy rainfall and an increased risk of flooding and landslides. Droughts may increase in arid and semi-arid regions, where higher rainfall is not able to compensate for the greater evapotranspiration. The increased risk of flooding under climate change has been assessed regionally and nationally (8). Coastal flooding will also increase if the sea level rises unless sea defences are upgraded appropriately (50).

Table 2. Serious floods in Europe in the 1990s

River(s)

Year

Fatalities

Damage costs

Remarks

Tazlau (Romania) 1998

Breakdown of the Tazlau dam

Ouveze (France)

Rhine/Meuse

Rhine

1992 Nearly 100 Not known Camp site 1993/1994 10 €1100 million

1994

1994/1995 None

Glomma and Trysil River Basins (Norway)

Pyrenean River

Oder, Labe, Vistula and Morava

Lena (Sakha, Russian Federation)

1995

1996

1997

1998

None

85 95

€ 10 000 million Catchment area covered by up to 60 cm of mud

€ 1600 million Evacuation of 240 000 inhabitants in the Netherlands

€ 300 million Largest flood since 1789

Not evaluated Camp site

€ 5900 million 195 000 people evacuated; great material loss

1300 million 51 295 people evacuated, roubles complete disruption of transport system, great material loss

Source: European Environment Agency (89), adjusted by Menne et al. (90).

Floods are the most common trigger for a natural disaster. Recent devastating floods in Europe affected the Czech Republic, France, Germany, Italy, the Netherlands, Norway, Poland, Romania and the Russian Federation.

Except for those generated by dam failure or landslides, floods are climatic phenomena influenced by geology, geomorphology, relief and soil and vegetation conditions (92). Floods may also be intensified by human alteration of the environment such as the drainage patterns from urbanization, agricultural practices, deforestation and the use of improper construction techniques. Weather and hy-drological processes can be fast or slow and can produce flash floods or more predictable, slowly developing river floods.

Flash floods have two characteristics. First, they follow a causative event (such as excessive rainfall in a catchment system or sudden release of water in a dam) within minutes or hours and with high velocity flows and great volumes of water. Second, with flooding commonly lasting less than 24 hours (93), they are accompanied by an extremely short warning and response time, with potential for great loss of life (94). Riverine floods usually result from rainfall or the melting of snow and ice, and the levels rise more slowly.

Survival Treasure

Survival Treasure

This is a collection of 3 guides all about survival. Within this collection you find the following titles: Outdoor Survival Skills, Survival Basics and The Wilderness Survival Guide.

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