Although known resources of oil will be depleted in about 32 years, most of the world’s transportation is still based on petroleum. Due to this dependency on oil the world has so far widely neglected the consequences of environmental pollution, which results especially when petroleum is burned in engines during combustion. However, currently the environmental impact comes more and more into focus as recent natural disasters and environmental research data indicate a global climate change with potentially devastating consequences for our biosphere. Though such variations can also be caused by processes within the Earth’s climate (e.g. through glaciation or interaction between atmosphere and oceans) as well as external forces (e.g. variations in solar radiation or Earth’s orbit), the ongoing climate change is regarded as mostly human caused.

Current studies clearly indicate that radiative forcing by greenhouse gases is the primary cause of global warming, followed by aerosols (particulate matter in the atmosphere), and land surface changes (irrigation, tropical deforestation, and agriculture). The greenhouse effect in turn, which is the warming produced as greenhouse gases trap heat, is largely influenced by the increase in carbon dioxide (CO2) levels due to emissions from fossil fuel combustion. It is thus human activities, which have exerted the substantial net warming influence on the Earth’s climate. In fact, ever since the industrial revolution in the 1850s the human consumption of fossil fuels has elevated CO2 levels from a concentration of about 270 parts per million (ppm) to more than 380 ppm today.

An ice coring study in the Antarctic, which analyzed air bubbles trapped in a 3.2 km long extracted core of frozen snow, indicates that such high greenhouse gas concentration as currently has never occurred even over the past 800,000 years. The results show unambiguously that CO2 has only varied between 180 ppm and the pre-industrial level of 270 ppm. This finding is inasmuch troublesome as the current level of about 380 ppm is expected to rise over more than 560 ppm until the end of the 21st century. Along with rising methane levels, these changes are anticipated to cause an increase in temperature of 1.4 to 5.6 Celsius.

If the amount of human generated greenhouse gases is not significantly reduced in the very near future, there are likely to be many devastating impacts of global warming. Naturally, intense heat waves will be more frequent, leading to more droughts and wildfires. More dramatically, warmer temperatures will further melt the polar icecaps. The Arctic Ocean for example could be ice free in summer already by the year 2050. In another example the flow of ice from glaciers in Greenland has already more than doubled over the past decade. With that also the risk increases, that a major ice sheet in Greenland or in West Antarctica collapses, either of which could raise global sea levels by approximately 6 meters (20 feet). Whether through melting or collapsed ice sheets, a significant rise in sea levels would devastate coastal areas worldwide and produce millions of refugees. Furthermore, the melt water from Greenland is of lower salinity, which could possibly halt the Gulf Stream and thus quickly trigger a dramatic local cooling in Northern Europe. Altogether, more than a million species worldwide could be driven to extinction by the year 2050. Warmer temperatures will also increase the occurrence of infectious tropical diseases such as malaria in regions, where formerly low temperatures would have prevented such spread.

If appropriate actions are taken soon, the effects of global warming can be successfully reversed. The key of any initiative will be to drastically reduce the emission of CO2 from fossil fuel combustion. Biodiesel can play a major role in this challenge because it cuts emissions of carbon monoxide (CO) by approximately 50% and CO2 by 78% on a net lifecycle basis. In fact, biodiesel is the only alternative diesel fuel that actually reduces major greenhouse gas components in the atmosphere. The use of biodiesel also significantly reduces the emissions of ozone-forming-hydrocarbons, hazardous diesel particulates, and acid rain-causing sulfur dioxide. Furthermore, it virtually eliminates visible smoke and noxious odors and is easily biodegradable so that spillage represents little danger to the environment.

Considering the potentially devastating impacts of global warming, the focus of future energy development must be changed towards renewable energy sources and on biodiesel especially for transportation fuel. In Thailand this objective has been clearly identified, which in turn already led to Royal Initiative Projects and Promotion Policies to establish a bio-fuel industry. The National Alternative Energy Policy states that by the year 2011, 8% of the nation’s energy consumption will come from sixteen alternative energy sources, including biodiesel and gasohol.