Glossary
Adaptation: Adjustments in natural or human systems in response to actual or expected climatic stimuli or their effects, which moderates harm or exploit beneficial opportunities. Various types of adaptation can be distinguished, including anticipatory, autonomous and planned adaptations.
Aquifer: A stratum of permeable rock that bears water. An unconfined aquifer is recharged directly by local rainfall, rivers, and lakes, and the rate of recharge will be influenced by the permeability of the overlying rocks and soils.
Atmosphere: The gaseous envelope surrounding the Earth. The dry atmosphere consists almost entirely of nitrogen (78.1% volume mixing ratio) and oxygen (20.9% volume mixing ratio), together with a number of trace gases, such as argon (0.93% volume mixing ratio), helium and radiatively active greenhouse gases such as carbon dioxide (0.035% volume mixing ratio) and ozone. Besides, the atmosphere contains the greenhouse gas water vapor, whose amounts are highly variable but typically around 1% volume mixing ratio. The atmosphere also contains clouds and aerosols.
Catchments: An area that collects and drains rainwater.
Climate: Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period ranging from months to thousands or millions of years.
Climate change: Climate change refers to a change in the state of the climate that can be identified by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer. It refers to any change in climate over time, whether due to natural variability or as a result of human activity.
Climate change Impacts: The effects of climate change on natural and human systems. Depending on the consideration of adaptation, one can distinguish between potential impacts and residual impacts.
Coral bleaching: The paling in color which results if a coral loses its symbiotic, energy-providing, organisms.
Deforestation: Natural or anthropogenic process that converts forest land to non-forest.
Drought: The phenomenon that exists when precipitation is significantly below normal recorded levels, causing serious hydrological imbalances that often adversely affect land resources and production systems.
Ecosystem: The interactive system formed from all living organisms and their abiotic (physical and chemical) environment within a given area. Ecosystems cover a hierarchy of spatial scales and can comprise the entire globe, biomes at the continental scale or small, well-circumscribed systems such as a small pond.
Erosion: The process of removal and transport of soil and rock by weathering, mass wasting, and the action of streams, glaciers, waves, winds, and underground water.
Extreme weather events: An event that is rare within its statistical reference distribution at a particular place. Extreme weather events may typically include floods and drought.
Freshwater lens: A lenticular fresh groundwater body that underlines an oceanic island. It is underlain by saline water.
Greenhouse gas: Greenhouse gases are those gaseous constituents of the atmosphere, both natural and anthropogenic, that absorb and emit radiation at specific wavelengths within the spectrum of infrared radiation emitted by the Earth’s surface, the atmosphere, and clouds. This property causes the greenhouse effect.
Groundwater recharge: The process by which external water is added to the zone of saturation of an aquifer, either directly into a formation or indirectly by way of another formation.
Infrastructure: The basic equipment, utilities, productive enterprises, installations and services essential for the development, operation, and growth of an organism, city or nation.
Ocean acidification: Increased concentrations of CO2 in seawater causing a measurable increase in acidity. This may lead to reduced calcification rates of calcifying organisms such as corals, mollusks, algae, and crustacean.
Plankton: Microscopic aquatic organisms that drift or swim weakly.
Sustainable development: Development that meets the cultural, social, political and economic needs of the present generation without compromising the ability of future generations to meet their own needs.
Tsunami: A large wave produced by a submarine earthquake, landslide or volcanic eruption.
Vulnerability: Vulnerability is the degree to which a system is susceptible to and unable to cope with, adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the character, magnitude, and rate of climate change and variation to which a system is exposed, its sensitivity, and its adaptive capacity.
Wetland: A transitional, regularly waterlogged area of poorly drained soils, often between an aquatic and a terrestrial ecosystem, fed from rain, surface water or groundwater. Wetlands are characterized by a prevalence of vegetation adapted for life in saturated soil conditions.