Mechanisms of Climate Change Impacts

Mechanisms of Climate Change Impacts
When thinking about information on adaptation technologies as described in the previous page, if one is to accurately grasp the need for these technologies in the coastal zones of the Asia-Pacific region, it is important to understand the mechanisms of climate change impacts in those zones. The flow described below is envisioned as an overarching framework for that understanding.
while adequately considering information that can be useful at the local level.
To begin with, "changes in climate factors" occur, such as air temperature rise, sea temperature rise, and sea level rise, followed by "primary impacts," such as flooding, inundation, coastal erosion, saltwater intrusion, and impacts on ecosystems. Next are the resulting "secondary impacts," such as impacts on agriculture and fisheries, and on land conservation. Finally, it is necessary to consider not only the primary and secondary impacts of climate change, but also the effects that arise from combinations of current environmental and societal factors. Based on impacts such as those mentioned above, the assumed impacts and technology needs are then compiled for each coastal type. Finally, is also important for national and local governments to consider the kinds of impacts climate change will have on future growth strategies and development plans.

Framework of the mechanisms of climate change impacts in coastal zones

Change in Climate Factors
  • Air temperature rise
  • Sea temperature rise
  • Sea level rise
  • Changes in tropical cyclones
  • Changes in precipitation
Primary Impacts
  • Inundation
  • Inundation / flooding
  • Coastal erosion
  • Saltwater intrusion
  • Ecosystem deterioration
Secondary Impacts
  • Impacts on agricuture, fisheries
  • Impacts on land conservation
  • Impacts on water resources
  • Impacts on industry
  • Impacts on urban services
Current Natural and Social Factors
  • Changes in topography
  • Changes in river flow, watercourses (rivers, dams, etc.)
  • Changes in land use and population density in coastal and low-lying areas
  • Situation of coastal development plan, coastal management plan
Impacts, by coastal type Impacts on future growth strategies, development plans

Climate change impacts and needs relating to the water environment sector

Change in Climate Factors
  • Temperature rise, aridification
  • Water temperature rise
  • Changes in amount of rainfall (increase, decrease)
  • Changes in rainfall patterns (increase in heavy rains)
  • Sealevel rise
Primary Impacts
  • Formation of oxygen-deficient water layers and increased frequency and intensity of red tides
  • Decreased water levels of rivers, dam reservoirs, and lakes
  • Increased proliferation of algae, bacteria, and fungi due to warmer water temperatures
  • Increases in cryptosporidium due to increases in heavy rainfall
  • Discharge of pollutants (organic matter, chemical fertilizers, pesticides, heavy metals, etc.) into water bodies due to increases in heavy rainfall
  • Increased turbidity in dams, lakes, etc. due to increases in heavy rainfall
  • Salinization and saltwater intrusion into groundwater, river estuaries, and arid land
  • Changes in ecosystems due to changes in water quality
Secondary Impacts
  • Impacts on fisheries due to eutrophication
  • Increases in water-borne diseases due to increases in heavy rainfall
  • Odors and deterioration of taste of chlorinated drinking water due to algae proliferation associated with increased water temperatures
  • Increased costs and problems for water supply treatment processes due to increases in cryptosporidium associated with increases in heavy rainfall
  • Increased costs and problems with supply of water due to resuspension of water bottom due to lowered water levels, and due to pollution/contamination associated with heavy rainfall
  • Deterioration of water quality due to dysfunction of water-related infrastructure during flooding
  • Decreases in available groundwater, etc., due to salinization
Natural and Social Factors
  • Industrial activity near water bodies
  • Land changes near water bodies
  • Increased in pollution loads from households due to increases in population
  • Increase in pollution load due to increased industrial activity
  • Lack or deterioration of infrastructure such as sewerage systems, community wastewater treatment facilities, septic tanks, etc.
  • Lack of adequate water supply infrastructure
  • Poor health and hygiene conditions
Needs and challenges
  • Development of basic regulatory systems and plans relating to water environment
  • Monitoring of water environment
  • Impact prediction and vulnerability assessments
  • Wastewater treatment (Johkasou, advanced treatment )
  • Fertilization management in agriculture/ fisheries technologies
  • Water-monitoring detection system for the presence of infectious disease
  • Securement of quality of drinking water
  • Techniques to reduce the duration of flooding-induced turbid water in dam reservoirs caused by heavy rainfall
  • Purification technologies
  • Prevention measures for salt water intrusion of groundwater
  • Economic incentives

Climate change impacts and needs relating to the water resources sector

Change in Climate Factors
  • Higher temperatures
  • Less rainfall
  • Changes in rainfall patterns
  • Melting of ice masses
  • Sealevel rise
Primary Impacts
  • Reduced flow volumes in rivers
  • Lower water levels in reservoirs and dams
  • Lower groundwater levels
  • Seasonal changes in water flows (prolonged dry season, etc.)
  • Changes in timing of snowmelt (e.g., occurring earlier)
  • Occurrences of mudflows and avalanches
  • Decrease in glacial melt water
  • Salinization of groundwater
  • Reduction of freshwater lens (on small islands)
Secondary Impacts
  • Lack of agricultural water
  • Lack of industrial water
  • Lack of water for domestic uses
  • Impacts on food production and export crops
  • Impacts on industrial supply chains
  • Appearance of constraints on social and economic development (small islands)
Natural and Social Factors
  • Decreased recharge capacity of land due to deforestation (rural and mountainous areas)
  • Decreased recharge capacity of land due to urbanization (urban areas)
  • Increased water demand for agriculture due to increased crop production
  • Increased water demand for industry due to increased industrial activity
  • Increased domestic water demand due to population growth
  • Increased water demand due to changes in lifestyles
  • Decline of traditional rainwater harvesting due to urbanization and increased demand for new construction
  • Lack and deterioration of infrastructure such as reservoirs and water supply networks, etc.
Needs and challenges
  • Development of basic regulatory systems and plans relating to water resources
  • Monitoring of water quantities, water resources
  • Impact prediction and vulnerability assessments
  • Water-saving technologies
  • Increasing the efficiency of water use (efficient use of irrigation, measures to control agricultural water leakage)
  • Review of water rights
  • Water conveyance technology
  • Rainwater harvesting
  • Rainwater storage and infiltration (groundwater recharge)
  • Use of reclaimed water
  • Desalinization
  • Flexible operation of dams (development and utilization of weather simulations)
  • Economic incentives (water pricing, effluent rights trading)