It is now almost 20 years since the Earth Summit in Rio de Janeiro, when governments around the world agreed that they must combat climate change, preserve the world’s biodiversity and limit damage to soils. But in these 20 years, the greenhouse gases that are causing climate change have built up rapidly, biodiversity has eroded and the use of natural resources has gone up 40%.
Outlining this in a report released to coincide with the annual summit of the United Nations Framework Convention on Climate Change – now going on in Durban, South Africa – UN Environment Programme (UNEP) Executive Director Achim Steiner said: "The report also underlines how, when the world decides to act, it can dramatically alter the trajectory of hazardous trends that threaten human wellbeing – action to phase out ozone damaging chemicals being a spirited and powerful example.”
Global warming is caused by the build-up of greenhouses gases – mostly carbon dioxide – in the atmosphere. The UNEP report points out that global carbon dioxide emissions continue to rise due to increasing use of fossil fuels, with 80% of global emissions coming from just 19 countries. The good news is that the amount of carbon dioxide emissions per $1 GDP has dropped by 23% since 1992, underlining that some decoupling of economic growth from resource use is occurring. But still, nearly all mountain glaciers around the world are retreating and getting thinner, with severe impacts on the environment and human wellbeing. Diminishing glaciers not only influence current sea-level rise, but also threaten the well-being of approximately one-sixth of the world's population. Sea levels have been rising at an average rate of about 2.5 millimetres per year since 1992.
Tracking energy trends since 1992, the report indicates that the contribution of renewable energy (including biomass) to the global energy supply stood at an estimated 16% in 2010. Solar and wind energy accounted for only 0.3% of the total global energy. But increased recognition of the need to move towards low carbon, resource efficient energy solutions can be seen in the 540% increase in investments in sustainable energy between 2004 and 2010. Due to the decreasing prices of the technologies and adoption of new policies, growth in biodiesel as a renewable energy source has jumped 300,000%, use of solar energy has increased by nearly 30,000%, wind by 6,000% and biofuels by 3,500%.
But the big problem remains – global use of natural resources rose by over 40% from 1992 to 2005. The report warns that, unless concerted and rapid action is taken to curb and decouple resource depletion from economic growth, human activities may destroy the very environment that supports economies and sustains life.
It says that despite the net reforestation now seen in Europe, North America and Asia Pacific, ongoing forest loss in Africa and Latin America and the Caribbean means that global forest area has decreased by 300 million hectares since 1990. The annual 20% rise in the number of forests receiving certificates for sustainable forestry practices shows that consumers are exerting influence on timber production. However, only around 10% of global forests are under certified sustainable management.
The report calculates that global food production has risen by 45% since 1992. These increased yields are heavily reliant on the use of fertilisers, which, while enriching soil fertility, can also have a negative impact on the environment, such algal blooms in inland and marine waters. The good news is that land used for organic farming is growing at an annual rate of 13%.
Another piece of good news is that the world will meet, or even exceed, the Millennium Development Goals target on access to drinking water – by 2015 nearly 90% of the population in developing regions will have access to improved sources of drinking water, up from 77% in 1990.
The Montreal Protocol on Substances that Deplete the Ozone Layer has been a shining success story of international cooperation to save the world. Over 90% of all ozone-depleting substances under the treaty were phased out between 1992 and 2009. Only a small number of countries still use leaded petrol and they are expected to make the switch over the next year or two.
The report expresses concern that the oceans are becoming more acidic. This could have significant consequences on marine organisms which may alter species composition, disrupt marine food webs and potentially damage fishing, tourism activities.
Another major area of concern is that biodiversity has declined by 12% at the global level and by 30% in the tropics.
The report also points out that as the world's population crosses seven billion, urban population has grown by 45% since 1992. Yet the percentage of slum dwellers has dropped from 46% in 1990 to a third in 2010, thanks to improved housing and sanitation. The number of megacities with at least 10 million people has grown from 10 in 1992 to 21 last year. But still, 1.4 billion people around the world have no access to reliable electricity or the power grid.
The authors of the report say that the lack of sufficient, solid data and monitoring systems to measure progress remains an obstacle to achieving the environmental goals set by the international community. The report highlights the missing pieces in our knowledge about the state of the environment, calling for global efforts to collect scientifically credible data for environmental monitoring.