The European Union has been a force for good on environmental issues, argues EU Environment Commissioner Stavros Dimas. By acting together, he says, Europe has achieved far more on climate change, water quality and pollution than individual countries could have managed acting alone.
Since 1972 when the first European environmental policy was launched, the EU has proved a highly effective framework for co-operation on the environment.
For more than 30 years, it has tackled the problems of acid rain, the thinning of the ozone layer, air quality, noise pollution and waste. It has banned pollutants such as lead in petrol.
Water policy is a case in point. Water is a vital resource in every respect; yet without a common European goal, it would be very difficult for many member states to achieve good water quality.
Countries and regions have to cooperate across administrative and political frontiers in the framework of common river basins. Today, the Rhine, once considered the "sewer of Europe", is again home to the salmon.
In 2000, the EU adopted the Water Framework Directive. This ambitious policy aims to ensure that all the different types of waters in the EU - rivers, lakes, groundwater and coastal waters - reach "good quality" status by 2015.
Another area where action at EU level has made a profound difference is biodiversity and nature protection.
Natura 2000, the most widespread and successful network of high value nature sites in the world, would not exist without the EU. It was established through EU legislation on birds and habitats and it now boasts more than 30,000 sites throughout Europe.
If current consumption and production patterns continue, we will need two planet Earths in 50 years' time
Without Natura 2000, the protection of key habitats and species would have been developed in an ad-hoc, non-coordinated manner.
While there is much work still to be done, there are many success stories involving emblematic species such as otters, beavers, bears, wolves, bitterns, corncrakes and several birds of prey.
Survival at stake
Successive EU treaties state that the EU must ensure a high level of protection of the environment, not just for the sake of the environment per se but for the sake of human health, and for our survival.
A good illustration of this is the new EU regulation on the Registration, Evaluation and Authorisation of Chemicals (Reach), which will come into force in June.
Reach will require chemicals in widespread use to be tested for their safety; the vast majority have never been through such testing.
Another success story is what the EU has achieved in the framework of the United Nations on the issue of climate change. No single EU country would be able to significantly influence global emissions of greenhouse gases, and acting alone would expose single countries to unfair competitive pressures.
The EU spearheaded the Kyoto Protocol, and its dedicated efforts ensured sufficient backing for the protocol to enter into force - in spite of the US and Australia withdrawing.
When the EU speaks with one voice, the rest of the world listens.
To help meet its commitments, the EU has created the biggest multinational environmental trading scheme in the world, the EU Emissions Trading Scheme (ETS).
The European Council has recently approved EU proposals aimed at securing a comprehensive global post-2012 agreement on climate protection.
This envisages developed countries collectively reducing their greenhouse gas emissions by 30% by 2020 compared with 1990, with a view to bringing them down by 60-80% by 2050.
Even without global co-operation, the Council set out a unilateral European target of a 20% reduction in emissions.
Biofuels are part of Europe's drive on renewable energy
Another key Council decision was a new ambitious EU energy policy featuring a commitment to 20% renewable energy.
This will deliver many of the needed reductions in EU emissions, while also improving the security of energy supply and competitiveness.
However, Europe is still not on the path of sustainable development.
If current consumption and production patterns continue, we will need two planet Earths in 50 years' time.
When our very survival is at stake, environmental policy cannot remain isolated; it must be integrated into all relevant policies.
Starting with agriculture - considerable progress has been achieved in this area over the last decade with the reform of the Common Agricultural Policy (CAP).
Reform of agricultural policy has helped birds such as the corncrake
Financial support is no longer linked to production. Direct payments to producers are underpinned by respect for a set of basic conditions linked to the environment, plant and animal health, and animal welfare.
Once again, European countries have achieved far more acting together than they could have done in isolation.
We now need to transfer a greater share of CAP funding to rural development, to help achieve our biodiversity and water goals and so that agriculture and forestry can contribute to climate change mitigation and adaptation.
Just as worrying as climate change is the rate of biodiversity loss.
The scientific evidence is unequivocal - biodiversity loss is taking place at a very fast rate, and mankind is to blame for this. Scenarios such as those developed by the Millennium Ecosystem Assessment suggest that the impacts of ecosystem degradation will be every bit as severe for mankind as those of climate change.
This is because biodiversity underpins the good functioning of ecosystems, which in turn provide goods and services such as food, fibre, nutrient cycling and pollination that are vital to human prosperity and wellbeing.
Nature reserves are one beneficary of EU environmental efforts
Taken together, these services are worth trillions of euros per year worldwide, and we cannot do without them.
In May last year, the Commission presented a strategy for halting the loss of biodiversity in Europe by 2010, and an EU action plan for the period up to 2013.
The action plan highlights, for the first time at EU level, the link between biodiversity and ecosystem services.
The EU's policies for protecting nature and biodiversity will have to become instruments to help biodiversity adapt to climate change, both inside and outside protected areas.
EU environmental policy has come a long way from the early days when it concentrated mainly on tackling point source pollution.
It now takes a broader view, targeting deeply rooted production and consumption patterns and insisting on the integration of environmental concerns into other policy areas.
We know that choosing inaction today will bring far higher costs in the long run
It is also moving from using prescriptive legislation to employing innovative, market-based and more flexible instruments, with the ETS being the prime example.
The environment on which we rely for food, health and prosperity faces an array of challenges, globally and in Europe.
These challenges must be met now, not ignored or left for later. Our citizens demand strong protection of their environment, and we know that choosing inaction today will bring far higher costs in the long run.
Stavros Dimas is Europe's Environment Commissioner
The Green Room is a series of opinion articles on environmental issues running weekly on the BBC News website