The hazy skies over the 2008 Summer Olympics have placed Beijing's air quality at the top of news headlines for more than a month. However, outdoor air pollution, whether in the form of visible haze or invisible ozone and carbon monoxide, is a problem in nearly every country in the world.

As world food prices reach record highs, concerns over agricultural productivity are mounting. Productivity growth has stagnated as the world’s population has continued to rise, and the wealth generated from economic development is further increasing demand for food. The use of food crops like corn and sugarcane for biofuels production exacerbates the situation. The United Nations estimates that agricultural output will have to rise 50 percent by 2030 to meet this increased demand

EarthTrends April 2008 Monthly Update

Before climate change dominated the environmental agenda, deforestation was a central concern for many reasons besides carbon. Forests contain 70 percent of the world's biodiversity, provide vital ecosystem services such as flood control and soil protection, and support the subsistence livelihoods of up to 300 million people, most of whom are poor. To date, efforts to combat deforestation have failed to stop rapid global forest loss, despite some localized successes. Between 2000 and 2005, roughly 13 million hectares of forest disappeared each year, with the largest losses occurring in the biologically rich tropical forests of the developing world (FAO, 2005).

The threat of climate change has created a new imperative--and renewed hope--to protect the values and services rendered by tropical forests. The Intergovernmental Panel on Climate Change (2007) estimates that deforestation contributes 15-20 percent of global greenhouse gas emissions (see Figure 1), yet the forestry sector was largely excluded from the Kyoto Protocol's first commitment period. With negotiations underway for a post-Kyoto agreement set to start after 2012, reduced emissions from deforestation in developing countries, popularly known as REDD, has emerged as a key issue.

Now home to half of the world's people, cities are increasingly at the forefront of our most pressing environmental challenges. While the current pace of urbanization is not unique in human history, the sheer magnitude of urban growth--driven by massive demographic shifts in the developing world--is unprecedented, with vast implications for human well-being and the environment. However, where cities pose environmental problems, they also offer solutions. As hotspots of consumption, production, and waste generation, cities possess unparalleled potential to increase the energy efficiency and sustainability of society as a whole.

In the last quarter century, China's breakneck economic growth has lifted over 50 million people out of poverty and tripled energy demand. Experts predict that China will surpass the United States to become the world's largest consumer of energy and fossil fuels soon after 2010. And because of its heavy reliance on coal, China already emits more carbon dioxide than any country on earth.

The rate and path of this energy growth is of enormous consequence for both China and the world. At stake are issues of global importance, including climate change and competition over dwindling oil resources. Perhaps more important for China, however, are domestic concerns such as severe urban air pollution, energy security, and sustained economic growth.

Global water consumption increased sixfold in the last century--more than twice the rate of population growth--and will continue growing rapidly in coming decades. Yet readily available freshwater is a finite resource, equivalent to less than one percent of the water on Earth. What's more, water and populations are unevenly distributed across the globe; arid and semi-arid regions receive only two percent of all surface runoff yet account for 40 percent of the global land area and house half of the world's poor. Finally, our existing freshwater resources are under heavy threat from overexploitation, pollution, and climate change. Given these trends, equitably providing adequate water resources for agriculture, industry and human consumption poses one of the greatest challenges of the 21st century.

Indoor air pollution causes 1.6 million premature deaths every year and afflicts nearly half of the world's population, predominantly the rural poor. This makes it the second leading environmental health threat in the world and a critical barrier to poverty alleviation in low-income countries. Yet this issue is rarely discussed outside of public health circles, probably because the health consequences of indoor air pollution are not immediate and can be difficult to trace. Thus, indoor air pollution remains a quiet and neglected killer, with lack of global awareness being one of the primary obstacles to the widespread implementation of existing, proven interventions.

Fossil fuel combustion and industrial processes release over six billion metric tons of carbon into the atmosphere each year. The consequences of these greenhouse gas emissions are often discussed in terms of rising global temperatures, but global warming is not the only threat from increased atmospheric concentrations of carbon dioxide (CO2). Ocean acidification, which occurs when CO2 in the atmosphere reacts with water to create carbonic acid, has already increased ocean acidity by 30 percent (Doney, 2006). Although the chemistry of this effect is well understood and not much debated, the full consequences of ocean acidification for marine ecosystems and human well-being are only beginning to be revealed.

The building and construction sector generates substantial social and economic benefits, employing over 111 million people worldwide and contributing approximately ten percent to the global gross domestic product (UNEP SBCI, 2007). At the same time, the built environment contributes significantly to global raw materials use, energy use, solid waste generation, and greenhouse gas emissions (see Figure 1). Attempting to address these sustainability issues, the rapidly growing "green building" industry is employing cost-effective and environmentally mindful construction practices that do not usually require new or costly technologies.

Until recently, most research and policy initiatives related to climate change have focused on ways in which societies can reduce their greenhouse gas emissions and prevent the worst effects of global warming. Current scientific evidence shows, however, that some human-induced climate change is now inevitable and is in fact already occurring. The question of which regions and groups are most vulnerable to this predicted climate flux and how they might adapt to it has thus become an important area of research, funding, and policymaking.