Natural hazards and us

If you were not already aware of the scale of the everyday threat from nature then I hope, by now, to have engendered a healthy respect for the destructive potential of the hazards that many of our fellow inhabitants of planet Earth have to face almost on a daily basis. The reinsurance company Munich Re., who, for obvious reasons, have a considerable interest in this sort of thing, estimate that up to 15 million people were killed by natural hazards in the last millennium, and over 3.5 million in the last century alone. At the end of the second millennium AD, the cost to the global economy reached unprecedented levels, and in 1999 storms and floods in Europe, India, and South East Asia, together with severe earthquakes in Turkey and Taiwan and devastating landslides in Venezuela, contributed to a death toll of 75,000 and economic losses totalling 100 billion US$.

The last three decades of the twentieth century each saw a billion or so people suffer due to natural disasters. Unhappily, there is little sign that hazard impacts on society have diminished as a consequence of improvements in forecasting and hazard mitigation, and the outcome of the battle against nature's dark side remains far from a foregone conclusion. While we now know far more about natural hazards, the mechanisms that drive them, and their sometimes awful consequences, any benefits accruing from this knowledge have been at least partly negated by the increased vulnerability of large sections of the Earth's population. This has arisen primarily as a result of the rapid rise in the size of the world's population, which doubled between 1960 and 2000. The bulk of this rise has occurred in poor developing countries, many of which are particularly susceptible to a whole spectrum of natural hazards. Furthermore, the struggle for

Lebensraum has ensured that marginal land, such as steep hillsides, flood plains, and coastal zones, has become increasingly utilized for farming and habitation. Such terrains are clearly high risk and can expect to succumb on a more frequent basis to, respectively, landsliding, flooding, storm surges, and tsunamis.

Another major factor in raising vulnerability in recent years has been the move towards urbanization in the most hazard-prone regions of the developing world. Within just a few years, and for the first time ever, more people will live in urban environments than in the countryside, many crammed into poorly sited and badly constructed megacitieswith populations in excess of 8 million people. Forty years ago New York and London topped the league table of cities, with populations, respectively, of 12 and 8.7 million. In 2015, however, cities such as Mumbai (formerly Bombay, India), Dhaka (Bangladesh), Karachi (Pakistan), and Mexico City will be firmly ensconced in the top ten (Table 1): gigantic sprawling agglomerations of humanity with populations approaching or exceeding 20 million, and extremely vulnerable to storm, flood, and quake. A staggering 96 per cent of all deaths arising from natural hazards and environmental degradation occur in developing countries and there is currently no prospect of this falling. Indeed, the picture looks as if it mightwell deteriorate even further. With so many people shoehorned into ramshackle and dangerously exposed cities it can only be a matter of time before we see the first of a series of true mega disasters, with death tolls exceeding one million.

Table 1 The predicted ten most populous cities in the world in 2015


1. Tokyo

2. Mumbai

3. Lagos

4. Sao Paulo

5. Dhaka

6. Karachi

7. Mexico City

8. Shanghai

9. New York

10. Calcutta


28,900,000 26,900,000 24,600,000 20.300.000 19,500,000 19,400,000 19,200,000 18,000,000 17,600,000 17,300,000

Source: Munich Reinsurance 1999

The picture I have painted is certainly bleak, but the reality may be even worse. Future rises in population and vulnerability will take place against a background of dramatic climate change, the like of which the planet has not experienced for maybe 10,000 years. The jury remains out on the precise hazard implications of the rapid warming expected over the next hundred years, but rises in sea level that may exceed 80 centimetres are forecast in the most recent (2001) report of the IPCC (Intergovernmental Panel on Climate Change). This will certainly increase the incidence and impact of storm surges and tsunamis and — in places--raise the level of coastal erosion. Other consequences of a temperature rise that could reach 6 degrees Celsius by the end of the century may include more extreme meteorological events such as hurricanes, tornadoes, and floods, greater numbers of landslides in mountainous terrain, and, eventually, even more volcanic eruptions (see next chapter).

So is the world as we know it about to end and, if so, how? A century from now will we be gasping for water in an increasingly roasting world or huddling around a few burning sticks, struggling to keep at bay the bitter cold of a cosmic winter? In the next chapter Iwill delve alittle further into the possibilities.

Continue reading here: Facts to contemplate

Was this article helpful?

0 0