The NASA Earth systems science initiative just entered its 20th year, and to mark the occasion, NASA held a symposium at the National Academy of Science to review some of the scientific accomplishments made possible through the endeavor. Over the course of the three day symposium, scientists presented their research and discussed the impact of the NASA earth systems science initiative on the current understanding for a wide range of social, scientific and economic issues.

The size and scope of actions necessary to address climate change can cause paralysis and inaction. In the absence of public policy, emissions would grow to around 60 billion metric tons of carbon dioxide by the middle of this century from current emissions of roughly 30 billion metric tons per year. In order to achieve climate stabilization, most analysis recommends an emission reduction target of 50% to 100% by 2050 from today's levels. Politically, there has been progress. The United States House of Representatives recently passed the climate and energy bill, known as the American Clean Energy and Security Act. The incredible difference between the do-nothing, status quo trajectory and these targets can be daunting. This month on EarthTrends we will give an overview of the most commonly discussed technologies and practices that get us from here to there as well as a consideration of the associated costs of implementing these solutions.

One of the major hurdles to implementing international environmental sustainability objectives is securing local connectivity to, and action for, a global cause. Local communities can struggle in job training, information services support, appropriate policy and legal framework creation, and resource allocation necessary for achieving these goals. Unsurprisingly, this is more likely to occur in developing countries where initiatives are often stumped by spending capabilities and financial allocations.

What may be the largest barrier to connecting communities to international environmental sustainability objectives is cultural integration. Already environmental sustainability is influencing our cultural lifestyle choices, from the food we eat to the way we travel. However, to what extent is it impacting how we are entertained?

The islands of Mauritius and Réunion contain endemic species found nowhere else in the world that are plagued by massive population decline. Before the 1500s, these islands were uninhabited by humans. Soon after the arrival of the first explorers, Dutch settlement and the introduction of non-native plant and animal species, biodiversity loss mushroomed (WRI 1989). Since the over 400 years following the first alterations in the islands' ecosystems, populations of native birds, reptiles, and trees have been driven to extinction.

The first evacuation of an entire people on environmental grounds has now begun in the South Pacific. Persistent flooding is causing the submergence of the Carteret Islands, a low lying atoll in Papua New Guinea, where the saltwater intrusion is also contaminating the islands freshwater supply and preventing the growth of crops. Despite attempts at battling the floods, including building a seawall and planting mangroves, the islands were declared uninhabitable by the government in 2005 and expected to be completely submerged by 2015. Now, the first few families have been relocated to Bougainville on the mainland as part of the initial stage of the evacuation process causing the Carteret Islanders to be labeled as the world's first environmental refugees.

This forced resettlement of a whole population draws attention to the inescapable reality of environmental displacement, an occurrence which will only become more commonplace as the impacts of climate change are felt around the world.

In March 2007, Earth Trends published a monthly update focusing on the uncertainty of the global biofuel industry. Since this publication, world fuel ethanol production has increased from 12 billion gallons in 2005 to an estimated 17 billion gallons in 2008. One of the key factors behind this rapid increase in production is the growth of the transportation sector. Global motor gas consumption increased by 21 percent throughout the world between 1990 and 2003. The four most prominent boosts occurred in the U.S., China, Japan, and Iran as shown in Figure 1.

Energy, has powered human development from the dawn of time. The energy from the sun fuels all life on Earth. The potential energy extracted from humans and animals forms the foundations on which our society has been built. The electrical and mechanical energy generated from natural resources such as fossil fuels, water, and steam have opened numerous avenues within industry, transportation and livelihoods. As science and technology progress and energy sources increase in efficiency and capacity so too do the limits of our capabilities.

However, just as energy has the potential to instigate development it can also act as one of the greatest barriers. While the poor can most benefit from improved access to energy sources, they are also the most likely to suffer from the effects of unsustainable energy use such as climate change, deforestation, adverse health impacts and desertification.

April 22nd, better known as Earth Day, is a perfect opportunity to bring the environment to the forefront and review some of the key global changes and trends impacting the world. So in honor of Earth Day the EarthTrends team has put together a few interesting statistics from our database.

Happy Earth Day!

Twenty-two years ago, the Montreal Protocol was adopted to protect the ozone layer from depletion. It was the first-ever international agreement on the regulation of chemical pollutants. (Carlowicz, 2009)

The Montreal Protocol was characterized by Kofi Annan as "one of the great success stories of international cooperation." As a recently released simulation of Earth without the Montreal Protocol shows, there would have been grim consequences for a business as usual approach. (See Figure 1.) Among other things, this simulation predicts an Earth with a dangerously insufficient ozone layer by 2050.

The relationship between economic growth and rising carbon dioxide (CO2) emissions is the chicken or the egg question of the climate change debate. A growth in industry, and hence emissions, will no doubt stimulate a country's Gross Domestic Product (GDP). Conversely, a higher GDP will often lead to a greater disposable income and higher standards of living which could manifest in more cars, more residential energy use and more consumption all of which will impact on a country's total emissions.