NATURAL ENVIRONMENT ENVIRONMENTAL IMPACTS AND NATURAL DISASTERS

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1 ENVIRONMENTAL IMPACTS AND NATURAL DISASTERS NATURAL ENVIRONMENT Environmental degradation intensifies disasters, thereby increasing the potential for secondary disasters: high windstorms are followed by floods and landslides, floods by drought, and drought by pest epidemics and famines. The damage to the environment caused by extreme weather events has escalated, increasing faster than population growth. It is also clear that developing countries are far more vulnerable than industrial countries to both catastrophic events and deterioration of the environment» (Munasinghe and Clarke, 1994). The recent ECLAC assessments of the damages caused by Hurricane Mitch in Central America conclude that the already severe effects of the rains were aggravated by man s previous actions, such as: deforestation, mainly on steep hillsides, inappropriate land use, and settlements on hillsides or on riverbanks and lakeshores. Similarly most of the damage by hurricane Lenny in Anguilla was caused by the location of tourism infrastructure in high risk environments. 1

2 Recognition of the causal links is an important first step but needs to be followed by a more detailed understanding of links and, eventually, a quantification of the impacts and an assessment of the subsequent economic implications. Caribbean and Central American environments have evolved in the presence of natural disasters. Therefore, the region's natural systems depend on such disasters for eco-system resilience and diversity. In consequence of disasters being an intrinsic part of the region's natural environments, the direct impacts in terms of stock losses of these natural systems should not be costed. Furthermore with few exceptions, these natural systems should be left alone to regenerate because human intervention may cause more damages. However, much of the region s ecosystems are significantly degraded, a process that is still continuing. Deteriorated ecological systems contribute to the severity of the impacts of natural disasters This increased vulnerability is translated in increased loss of life and in direct, indirect damages and secondary effects. Such effects tend to be estimated in the assessment of the economic and social sectors where they manifest themselves. 2

3 The cumulative loss of natural capital in degraded systems needsto be addressed if intervention would reduce the vulnerability of a society to disasters. Such interventions may include restorations of the degraded systems, or, when this is not possible or is perceived to render a society still too vulnerable, man-made infrastructure may also be considered as an option. Anderson notes that although vulnerability has its costs, vulnerability reduction has its costs as well. However, if the costs of environmental vulnerability are not wel known or understood little or no meaningful environmental vulnerability investments can or will be undertaken because cost benefit assessments may be difficult to carry out.» In Munasinghe and Clarke (1994). Another factor which needs to be considered with degraded natural systems is that much of their functioning has been lost and they have become so weak that any additional stress, such as that caused by a natural disaster, may result in irrecoverable damage (e.g. coralreefs around Jamaica). This may render a country even more vulnerable to future natural disasters. Because of the irrecoverable damage, ecosystem restoration may no longer be feasible and man-made infrastructure works may have to be carried out to reduce vulnerability. 3

4 A final aspect of environmental impacts is that there are situations when human structures or activities may be at high environmentalrisk. Examples are: the construction of houses in gullies, steep hillsides or flood prone areas or, the construction of hotels and residences on the ocean s edge near high water marks. We will approach those functions of the natural environment that benefit current or future human uses. The range of goods and services that a natural system provides is wide and all the services are not necessarily known or identified. Hence, such identification may already be an under-estimate. Typically, the identification of the goods and services has to be carried out per eco system. HURRICANE KEITH (WAVES, WIND RAINFALL) IMPACTS ON: Wildlife (birds) Dead birds Habitat destruction (nesting and feeding sites Water quality Turbidity Floatingseagrass contaminatio n Beaches Erosion Sedimentatio n plumes Debris Sea-grass beds Mechanical damage Excess Situation Smothering Mangroves Defoliation Uprooting of isolated trees Coral Reef Mechanical damage in lcoatedareas Other impacts to assess (smothering, Mainland: Flooding Changes in Water courses ENVIRONMENTALGOODS AND SERVICES INVOLVED TOURISM (RECREATION) HABITAT TOURISM (RECREATION) NAVIGATION FISHING TOURISM (RECREATION) LAND FISHERIES SUPPORT OF MARINE LIFE COASTAL PROTECTION WILDLIFE HABITAT FISHERIES COASTAL PROTECTION TOURISM FISHERIES UNIQUE ECOSYSTEM HIDROLOGICAL REGULATION 4

5 ENVIRONMENTAL DAMAGE ECONOMIC ASSESSMENT SCHEME HURRICANE KEITH ENVIRONMENTAL CHANGES IMPACTS UPON PHYSICAL IMFRASTRUCTURE Damage to tourist infrastructure Buildings Piers Boasts Protection Loss of boats and fishing gear Overflow of sewer lagoons and inundation of septic tanks Loss of water quality Birds habitat destruction Damages to seagrass beds HEALTH EFFECTS DAMAGES TO FISHING SECTOR DAMAGES TO TOURISM BUSINESS INDIRECT DAMAGE Valuation of environmental services lost included in the damage assessment of: Tourism sector Fisheries Water sanitation Damages to mangroves Beach erosion DAMAGES Mangroves Beach clean-up Beach erosioin Coral reef NO ESTIMATION OF DIRECT DAMAGES Identification of relevant eco systems. Ecosystem Ecosystem 1 Ecosystem 2 Ecosystem 3 Level of degradation Impact of disaster (qualitative) Coastal and marine ecosystems are of particular importance to sm all Caribbean countries. In recent years qualitative and sometimes quantitative assessments of the impacts on coastal ecosystems, in particular beaches, have become increasingly available as a consequence of the activities of COSALC, the OECS NRMU and national coastal zone management programmes. Apart from increasing knowledge on coastal processes these programmes provide baseline data against which damages can be assessed. 5

6 Much less progress has been made in evaluating impacts on marine environments although at times cursory evaluations may be available. From a human perspective a classification of the environmental goods and services provided by an eco-system may assist the evaluator. An example for forests is shown in the first column of worksheetii. Identification of services and impacts: forests Environmental Impact by Valuation Service disaster method (quantitative) Direct Use Timber market Fuelwood and Market charcoal Producer prices Food and fish Consumer prices Producer prices Other business market products Non-wood products Agricultural market production Recreation and Travel cost tourism Bio-prospecting Source of valuation/ proxy Market or proxy price Estimated Secondary Impact Indirect use Absorption of waste Recycling nutrients Watershed protection Soil quality and erosion resistance General and life support Genetic pool Climate regulation Carbon fixing Habitat Scientific data Source: Column 1: Pearce and Moran (1994), Lampietti and Dixon (1995), ECLAC Other columns ECLAC/CDCC 6

7 After the identification, the change in the provision in goods and services need to be quantified in volume and or monetary terms. A problem with many environmental goods and services is that markets do not exist. Conceptually, the total economic value of an environmental asset is the sum of the use and non-use values. Use values include direct use or directly consumable outputs which may (like timber in a forest) or may not (like collecting home consumption) have a direct market price. Other components of use values are indirect use, which are the functional benefits, and option values. The latter emphasizes future benefits and includes biodiversity and conserved habitats. Examples of indirect use are watershed protection, storm water protection etc. Non-use values include bequest values and existence values. Chart II Environmental impact A SAMPLE VALUATION Measurable change in production Change in environmental quality Yes No Habitat Air and water quality Health effects Recreation Nondistorted market prices available? Yes No Usechange-in Usesurrogate productivity market approach approachesap ply shodow prices to changein production Opportunity-cost approach Replacement-cost approach Land-value approach Contingent valuation Cost-effectiveness of prevention Preventive expenditures Replacement/ relocation costs Sickness Death Loss of CEA of earnings prevention Medical Human costs Capital Travelcost Contigent valuation Aesthetics, Biodiversity, Cultural, Historical Assets Contingent valuation Source: Dixon, et.al (1994) 7

8 In general, the analyst will not have the time (or the resources) to apply any of the recommended techniques, apart from the change in productivity approach which is implicit in much of the approaches of the manual. At the same time, excluding non-market values may significantly underestimate the cost and benefits of the impacts. For example, Lampietti and Dixon (1995) estimate that non timber benefits of forests range from 50 to 67 percent of the total benefits. The use of proxy variables needs to be explored. Examples of forest values in Latin America and the Caribbean US$/ha/year Location Value Comments Brazil Amazonia 5 Brazil nut and rubber Guatemala (Maya 10 Chicle, xate, all spice reserve) Brazil Western 5-16 Amazonia Peru (Iquitos) forest gardens Peru 20 Latexes and fruits only Belize Medicinal plants Brazil Amazon 59 Kernel, charcoal, babassu palm Ecuador Amazon Fruits, medicine potential extraction Brazil Combu Island 79 Wild cacao, açai, rubber Brazil 97 Brazil nuts Brazil Para 110 Açai Mexico Vera Cruz 116 Fruits, housing materials, medicines Peru Jenaro Herrera 167 Wild camucamu Peru 422 Net value of the inventory of 1 ha. Venezuela 1 Caiman harvest Mexico 8 Ecotourism Costa Rica Monte 52 TCM Verde Note: Many of these values are not mutually exclusive. Source: Lampietti and Dixon 8