23 Ways The World Has Changed Since The First Environmental Summit In Rio

saudi arabia

Photo: UNEP Report 2011

20 years after the first Earth Summit in Rio de Janeiro, world leaders, policy experts and environmentalists are in Brazil for the Rio+20 United Nations Conference on sustainability.   The world has seen some big environmental changes over the past two decades, including rapid population growth, land degradation and biodiversity loss.   

In 2011, the United Nations Environment Program prepared a report to illustrate how the planet has transformed since 1992. We’ve highlighted the most fascinating trends. 

There are about 1.5 billion more people in the world, an increase of 27%

The number of megacities (cities with at least 10 million people) has more than doubled since 1990. Tokyo is still the largest megacity with nearly 37 million people, more than Canada's total population

The population of China's Pearl River Delta has tripled to about 60 million people

The number of passenger trips by aeroplane has doubled

The number of mobile phone users has increased from 23 million to 5.4 billion; the number of Internet users has increased from 10 million to 2 billion

The average person eats 20 pounds more meat each year

Carbon dioxide emissions increased 36%, from about 22 billion tons to 30 billion tons

Cement production is the fastest-growing source of carbon dioxide emissions

The average temperature on Earth has increased by .4°C

The 10 hottest years since records began in 1880 all occurred after 1998

Oceans have become more acidic

Mountain glaciers around the world are retreating and getting thinner

Arctic sea ice has declined 35%

Forest area decreased by 300 million hectares, an area larger than Argentina

Enormous portions of the Amazon rainforest have been cleared for cattle pastures and farms

Biodiversity in the tropics has dropped by 30%, largely due to deforestation

Plastic production grew 149 million tons, up to 265 million tons in 2010

The number of reported natural disasters has doubled from around 200 to over 400 per year

Massive irrigation projects turned Saudi Arabia into an exporter of food

Global fish stocks have dropped dramatically

Tuna catches increased by more than 1,000 tons, pushing some species to the brink of extinction

Electricity and heat generation increased by 66%, a much larger increase than the global population

The rising price of oil has led to an investment boom in the Alberta Oil Sands (an estimated $40 billion was invested in 2010 alone)

Learn more about one of the most pressing environmental issues...

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