|Natural Disasters in South East Asia and Bangladesh - Vulnerability Risks and Consequences (Centre for Research on the Epidemiology of Disasters - International Center for Training Exchanges in the Geosciences, 1998, 83 p.)|
The assessment of the natural disasters in Bangladesh and the other six target countries in South East Asia since the beginning of the century could be nothing but partial. Except the data concerning the direct consequences of natural disasters, very little information have been collected. The number, nature and cumulated effects of the minor events are difficult to estimate because of the insufficient data. The quality of the information collected is reduced by the political instability in some of the countries and varies as time goes by. However, the information compiled in the last 25 years is more complete and therefore more reliable.
Given these limitations, the first observation that can be made is the considerable effect that the natural disasters have in the area of study especially in a world-wide frame of reference. Despite the fact that the 7 countries occupy 1.7% of the total continental surface area with 6.7% of the world population, up to 12% of the events and more than 20% of the deaths and affected people have been recorded in the region on a world wide scale in the last 25 years.
Over the century, 700 disasters have occurred in the region of which 158 (23%) occurred between 1900 and 1979 and 542 (77%) between 1972 and 1996. These data and that concerning the deaths and affected people appear to show that the natural disasters are becoming more frequent and are also causing heavier consequences though one needs to be cautious about the limitations mentioned above concerning the availability of data.
The Philippines are unquestionably the country that has had the greatest number of disasters. Nearly 50% of the events have been recorded on these Islands. On the other hand, it is in Bangladesh that the greatest number of human deaths and affected people have been recorded. In the period between 1972 and 1996, two thirds of the affected people and about 80% of the deaths were from Bangladesh. These estimates are even greater on a century scale. The five other countries have the number of events adding up to 26% in the same period during which 5% of the deaths and 18.5% of the affected people were also recorded. The raw data nevertheless give very high values for all the countries in question in terms of the number of deaths and the affected people.
It is even more difficult to establish an economic assessment of the natural disasters in the 7 countries because of incomplete data which are not synthetic and that have variable estimations according to the different sources. It however appears very clearly that the natural disasters have deep-seated repercussions in the economic development of these countries (GDP, Public finance, Foreign trade, Price indexes...). Quite often, the GDP proportion affected by natural disasters goes beyond the 10% limit and is sometimes a result of one unique event (for example Bangladesh in 1988 and 1991).
Therefore the damages hit the 7 countries economic development particularly in some key sectors. Agriculture appears to be the most vulnerable activity because of its important role in the creation of national wealth and because of the needs of the population. The economic consequences, too, affect the activities linked with international trade (like export agriculture, tourism, craft and industrial activities) all of which have been rendered essential because of the national debts of the different countries. The development of these activities has called for the development of the transport system. The transport systems are particularly vulnerable as can be seen in the various examples giving the state of damage in this domain. Finally, the housing sector is one of the sectors most hit by natural hazards. A privileged relationship between the precarious settlements and the different sectors of the countries with a higher frequency and/or intensity of events has been clearly established, The effects of the natural disasters that the countries in the region have experienced are continuous and consequently have a particular tendency of increasing foreign dependence.
The analysis of the natural hazards in the region shows that there are a great variety of natural phenomena that have a great destructive potential. The hydro-meteorological phenomena (cyclones, floods, and droughts) largely dominate. All the 7 countries studied considered as a whole were above all affected by cyclones (up to 60% of the 700 events recorded between 1900 and 1996) and more than 25% of the events are floods. The other events show much lower frequencies, always less than 5%. In comparison with the other phenomena, there are many more deaths and affected people registered for floods and cyclones; approximately 95% of the deaths and affected people result from these two destructive phenomena.
According to the nature and variety of the hazards, three country groups have been distinguished:
* The Philippines and Bangladesh
These two countries both have a very high degree of exposure to various hazards but show notable differences. Bangladesh is affected almost only by hydro-meteorological phenomena (cyclones, floods, and droughts), while different hazard types including earthquakes, and volcanic eruptions are potentially present in the Philippines.
* Myanmar, Vietnam and Laos
Myanmar, Vietnam and to a certain extent Laos are affected by the majority of hydro-meteorological and induced (mass movements) phenomena and have a potentially high degree of exposure though lower than that for the above mentioned group of countries. The earthquake threat is small in all the countries except Myanmar. The threat of volcanic activity does not exist.
* Thailand and Cambodia
The principal danger in these countries is flooding.
A comparison between the potentialities of the different natural hazards and events that have occurred during the century shows that there is a strong correlation between the two, even though some phenomena like earthquakes, floods and droughts are likely to be more frequent and more a plague for certain countries than was reported during the previous times (for example Laos and particularly Cambodia).
On the other hand, some more significant distortions appear in comparing the frequency maps, number of deaths and affected people. The most obvious distortions have been observed in the Philippines and Bangladesh. There are a more significant number of disasters in the Philippines, but proportionally many more deaths and affected people in Bangladesh.
Besides the physical component, the above facts highlight the importance of the human factor and vulnerability.
The analysis of the vulnerability of the countries in the region was carried out using a selection of socio-economic indicators (wealth, health and education) and demographic criteria (density, population growth). The juxtaposition of these two series of indicators allowed to establish a classification of the countries in terms of vulnerability though this classification remains a global one. The classification is given below:
* All the indicators for Bangladesh are unfavourable and it is therefore the most vulnerable country.
* Cambodia is mainly penalised by the socio-economic factors.
* Laos and Myanmar are vulnerable mainly because of the socio-economical indicators though to a lesser degree than those above.
* Vietnam and the Philippines seem to be slightly less vulnerable than Laos and Myanmar. Vietnam is mainly vulnerable because of its weak socio-economic indicators; the Philippines because of demographic criteria.
* The majority of the indicators for Thailand are distinctly more favourable than those of the other countries. It is therefore the least vulnerable country.
Vulnerability and natural hazards data have been crossed and used to define global risk levels. This was done by considering the relative variety and intensities of the natural hazards, the natural disaster frequencies, and the socio-economic and demographic criteria of vulnerability. Three groups of countries in decreasing order of vulnerability have been determined and are given below:
* The maximal risk level is reached by Bangladesh and the Philippines. The situation in these two countries is however distinctly different. In the Philippines, the risks are a result of all the different hazard types (however cyclones and floods have a dominating frequency), of their high intensity, past or potential, and of a relatively high vulnerability. On the other hand, the destructive phenomena are less varied in Bangladesh (essentially of hydro-meteorological origin) and their frequency slightly low, however the vulnerability is very high. This explains largely the greater number of deaths and affected people in this country in the past decades despite the relatively lower number of events registered.
* Myanmar, Vietnam, Laos and Cambodia all have a high risk level but this value is clearly lower than that of the Philippines and Bangladesh. Here again, a slight difference is to be introduced. The variabilities of the hazards are notably more penalising for Myanmar and Vietnam; the two other countries however show a slightly higher vulnerability. In all these countries the main risk comes from hydro-meteorological hazards even though Vietnam and even more Myanmar are concerned also by earthquake risks.
* Thailand is different from the other countries by its relatively lower risk level (the risk is referred to as being moderately high). The destructive phenomena, floods in particular, are not rare in this country. Cyclones occasionally might affect the country. The degree of exposure to natural hazards is thus globally comparable to that of the countries in the previous group. On the other hand, the level of vulnerability is clearly much lower as shown by most of the selected socio-economic and demographic indicators. This implies that the ability to respond to risks or crises or at least an ability to absorb the consequences of disasters is appreciably higher here than in the other countries.
The fourth part of the report considers that the global approach of risks is insufficient in as much as the diversities in each country are not taken into consideration. A synoptic assessment of the risks, on a national scale, was therefore carried out. It enabled the identification of a number of territories prone to risks. It was necessary to identify them because of differences in their physical (hazards) and human (occupation and land use, sociopolitical variations) characteristics in the perspective of actions adapted to prevention and preparedness.
With regard to the physical and human criteria, five types of territories prone to risks have been determined. These five types are present either partially or wholly in each of the countries.
* The deltas
The deltas are characterised by a physical environment which increases the danger by the conjunction of cyclones, river floods, high tides, storm surges if not local tsunamis. The deltas because of the rice-growing potential or the presence of major cities that rapidly increase their infrastructure and activities, often have very high population densities. International openings tend to increase the vulnerability by shattering, among others, the earlier traditional measures of risk management. On the other hand, the dominating ethnic groups are in the majority. This factor may, to a certain extent, reduce the vulnerability.
* The coastal plains
The coastal plains are in nature quite similar to the deltas. They are both subject to the same intensities of the destructive phenomena. There is little access, often difficult, to the coastal plains. Except in Bangladesh and with local exceptions, the population density is, on the whole, much lower than in the delta areas. In the same way, the international investments are restricted, selective and vary from one country to another. With the exception of Vietnam, the minority ethnic groups represent a high percentage of the population.
* The inland basins
The inland basins are mainly affected by river floods and droughts. Like in the case of deltas, high population densities are associated with such areas as a result of the presence of historical or present capital cities (in the case of Laos) and an irrigated rice growing activity. The major ethnic group of the countries largely dominates but the international openings are more restricted here than in the deltas. They however vary according to the country. This type of territory is still largely dominated by rural agricultural activity; this is probably why the perception of flood risks is weakened, when droughts are mentally dreaded.
* The coastal mountains
The coastal mountains are directly concerned by cyclones, flash floods and mass movements. These mountains are still associated with the minority ethnic groups who often practice the slash-and-burn cultivation. The access to these mountains remains difficult even though the coastal proximities have sometimes given rise to commercial cultivation. The frequent opposition of the minority groups to the central authorities is also an important vulnerability factor.
* The inland mountains
These mountains are safe from the very strong cyclones. They, however, may experience droughts and are sensitive to flash floods and mass movements. The mountains are occupied by great numbers of the minority ethnic groups who are poorly controlled by the central authorities. The population density is limited and the mountains are far from being easily accessible. There are some very punctual projects in the area that will open the area especially towards China. This will, however, depend on the development of international relations which are considered to be strained in the area.
It is difficult to establish a hierarchy in terms of risks of the 5 territories. Each of the territories has specific types of natural hazards and particular forms of vulnerability even though it is easy to regroup the deltas and coastal plains on one side, and the coastal mountains and inland mountains on the other, and distinguish the inland basins. Therefore a typological classification of zones prone to risks is proposed here more than an attempt of hierarchical organisation based on risk levels. This approach aims at giving a basis of reflection and decision making for some of the solutions that would reduce the risks that cannot be standardised on a national scale but be adapted to the different types of situations.
This being stated, it might be possible to establish priorities. Taking all the human and physical criteria together, the deltas are logically within the very highest risk zones. For the other territories, the hierarchical organisation depends on the criterion considered. Considering the demographic criteria (population size and densities), the inland basins are of main concern. On the other hand, the risks in the coastal plains appear more significant given the striking diversity and potential intensity of the natural hazards alone. Basing on the sociopolitical factors (among others the minorities groups), it is the coastal or inland mountains that appear to be the areas of high risk because of the vulnerability. From this point of view the reduction of the vulnerability can not be a simple technical task. The determination of the priority sectors prone to risks cannot therefore be based on scientific, physical or human criteria only, but also on political choices and considerations.