The population continues to grow, and more and more people have to live on the same area and from the same amount of raw materials. Between now and 2025, another 3 to 4 billion people will be added to the planet's population, mainly in countries which are least able to handle the consequences of this population growth and the accompanying development. This will put the Earth under tremendous pressure - just imagine the large-scale deforestation, the loss of nature areas, environmental pollution, climate change, and so on.
This might well have disastrous consequences - unless the economic development and management of the Earth's raw materials is placed on a sustainable basis. The past few decades have seen a growing awareness that the Earth is a single living whole, and that what happens in one place can have major consequences on the other side of the globe. El Niño and the greenhouse effect illustrate this beautifully.
Authorities throughout world are beginning to understand this,
and have therefore concluded a number of international treaties
and conventions, such as the Climate
Treaty, the Kyoto
Protocol for reducing the emission of greenhouse gasses,
Convention for protecting the ozone layer, the UN
Convention on biological diversity, etc.
Satellites are the ideal - indeed, often the only - instrument
for studying world-wide processes, interactions between oceans,
continents and the atmosphere, monitoring changes over vast
regions, and acquiring new insights into how everything fits
together. They are used to monitor vegetation, map land-use
changes, measure ozone concentrations, monitor the temperature
of the oceans, etc.