UN SPIDER: How space-based information can support measures for climate change mitigation and climate change adaptation

Climate change represents a global threat to the economic, social and environmental dimensions of sustainable development. In December 2015, world leaders will convene in Paris, France, to agree on a universal agreement on climate change. This new agreement will address climate change mitigation, mainly through the reduction of greenhouse gas emissions, as well as the capability of countries and societies to adapt to the realities of climate change, such as extreme weather events. It will also address how to cope with climate change related losses and damages.

Satellites offer a unique way of gathering data on essential climate variables at the global level which may be too difficult, too costly or impossible to gather using in-situ approaches. Such variables include atmospheric, terrestrial, and oceanic aspects, inter alia: sea-level rise, deforestation trends, carbon emissions, and the melting of polar ice caps and glaciers.

For example, innovative technologies such as NASA’s OCO-2 mission or the French-German MERLIN satellite are able to probe the atmosphere for concentrations of methane or carbon dioxide, the two main contributors to the greenhouse effect.

Another example of space technologies for climate change mitigation is the monitoring of deforestation and the health of our ecosystems. Forests as well as healthy wetlands and other types of natural land covers play a decisive role on climates, because they are important factors in carbon sequestration acting as effective carbon sinks. However, monitoring large forest areas or other ecosystems from the ground requires a lot of time and resources. Satellites on the other hand can monitor such areas continuously over long periods of time. They can measure greenhouse gas emissions, provide data for forest inventories (for example through classification by age, vegetation and health of vegetation), assess changes in the extent of forests, and estimate anthropogenic emissions by sources. Thus, satellites can greatly support efforts such as the UN’s REDD+ mechanism to reduce emissions from deforestation and forest degradation in developing countries.

Satellites can also monitor variables that help societies better adapt to the realities of climate change. For example, through monitoring sea level rise due to increases in the subsurface ocean temperature. Climate change-related phenomena such as melting mountain glaciers and polar ice caps further contribute to the phenomenon. Sea level rise is by no means evenly spreading on the globe; the levels can vary greatly. For instance, Small Island Developing States in the Pacific seem to be more affected than the Pacific coast states in North and South America. Satellites can observe sea level developments through radar altimetry measurements and sea surface temperature assessments, which are then combined with in situ observations.

Floods, droughts and storms are closely linked to climate stimuli such as changes in temperature and precipitation, including rain, hail or snow which can be continuously monitored by satellites. This data can then be used to assess long term trends and support early warning systems.

Satellites can also measure water levels for freshwater bodies as well as assess the saturation of soils which are important indications related to droughts. Droughts and high temperatures resulting in part from climate change impacts can lead to devastating wild fires. Sensors such as the Moderate Resolution Imaging Spectroradiometer (MODIS) are able to detect fire locations by identifying hot spots.

Additionally to observing (hydro-) meteorological variables, satellites can also track social trends relevant to climate change, such as the increasing exposure of vulnerable communities to the adverse effects of a changing climate and help build more resilient cities and societies. For example, satellite data can help in urban planning by identifying settlement areas and assessing whether those areas are particularly exposed to sea level rise, flooding or drought.

Source: UN-SPIDER Newsletter 2/15: Space-based Information for Post-2015 Sustainable DevelopmentClimate change represents a global threat to the economic, social and environmental dimensions of sustainable development. In December 2015, world leaders will convene in Paris, France, to agree on a universal agreement on climate change. This new agreement will address climate change mitigation, mainly through the reduction of greenhouse gas emissions, as well as the capability of countries and societies to adapt to the realities of climate change, such as extreme weather events. It will also address how to cope with climate change related losses and damages.

Satellites offer a unique way of gathering data on essential climate variables at the global level which may be too difficult, too costly or impossible to gather using in-situ approaches. Such variables include atmospheric, terrestrial, and oceanic aspects, inter alia: sea-level rise, deforestation trends, carbon emissions, and the melting of polar ice caps and glaciers.

For example, innovative technologies such as NASA’s OCO-2 mission or the French-German MERLIN satellite are able to probe the atmosphere for concentrations of methane or carbon dioxide, the two main contributors to the greenhouse effect.

Another example of space technologies for climate change mitigation is the monitoring of deforestation and the health of our ecosystems. Forests as well as healthy wetlands and other types of natural land covers play a decisive role on climates, because they are important factors in carbon sequestration acting as effective carbon sinks. However, monitoring large forest areas or other ecosystems from the ground requires a lot of time and resources. Satellites on the other hand can monitor such areas continuously over long periods of time. They can measure greenhouse gas emissions, provide data for forest inventories (for example through classification by age, vegetation and health of vegetation), assess changes in the extent of forests, and estimate anthropogenic emissions by sources. Thus, satellites can greatly support efforts such as the UN’s REDD+ mechanism to reduce emissions from deforestation and forest degradation in developing countries.

Satellites can also monitor variables that help societies better adapt to the realities of climate change. For example, through monitoring sea level rise due to increases in the subsurface ocean temperature. Climate change-related phenomena such as melting mountain glaciers and polar ice caps further contribute to the phenomenon. Sea level rise is by no means evenly spreading on the globe; the levels can vary greatly. For instance, Small Island Developing States in the Pacific seem to be more affected than the Pacific coast states in North and South America. Satellites can observe sea level developments through radar altimetry measurements and sea surface temperature assessments, which are then combined with in situ observations.

Floods, droughts and storms are closely linked to climate stimuli such as changes in temperature and precipitation, including rain, hail or snow which can be continuously monitored by satellites. This data can then be used to assess long term trends and support early warning systems.

Satellites can also measure water levels for freshwater bodies as well as assess the saturation of soils which are important indications related to droughts. Droughts and high temperatures resulting in part from climate change impacts can lead to devastating wild fires. Sensors such as the Moderate Resolution Imaging Spectroradiometer (MODIS) are able to detect fire locations by identifying hot spots.

Additionally to observing (hydro-) meteorological variables, satellites can also track social trends relevant to climate change, such as the increasing exposure of vulnerable communities to the adverse effects of a changing climate and help build more resilient cities and societies. For example, satellite data can help in urban planning by identifying settlement areas and assessing whether those areas are particularly exposed to sea level rise, flooding or drought.

Source: UN-SPIDER Newsletter 2/15: Space-based Information for Post-2015 Sustainable Development