Environment

Self-described conservatives eschew efficient light bulbs when they come with green messages.

For years, Hollywood has celebrated Earth Day in order to raise awareness about environmental issues and to strike up a memorable dialogue about sustainable practices. And the film studios’ embrace of Earth Day has only strengthened over time. From PSAs to Paramount’s new micro-turbines, we take a look at the industry’s dedication to spotlighting one of the most important advocacy dates on the calendar. In 1990, the holiday got a pretty big boost from Hollywood when Time Warner called on some of their favorite talent to hammer home proactive things Americans could do to reduce their footprint on the planet. (Our favorites? A pony-tailed Kevin Costner teaching Meryl Streep how to recycle and Neil Patrick Harris as Doogie Howser giving a press conference about the health of his patient, "Mother Earth.") But in 2013, the film business's efforts have far exceeded PSA productions, and the good news is that a lot of progressive practices like electric car fueling stations, composting, a ban on plastic bags in commissaries, and required carbon emission reporting have become all but de rigueur on most major lots. As each of the main studios shoot to achieve "100% sustainable" status in the coming years, the pressure is on to determine creative ways to be the first to get there, and then some. In honor of Earth Day, we take a look at some of the ways Hollywood is committed to 'greening' up their practices:

How high can the CO2 concentration in the air go? It is a bit like looking at the stock market except that the CO2 does not go down. For the first time in human history, concentrations of the greenhouse gas carbon dioxide (CO2) could rise above 400 parts per million (ppm) for sustained lengths of time throughout much of the Northern Hemisphere as soon as May 2013. To provide a resource for understanding the implications of rising CO2 levels, Scripps Institution of Oceanography at UC San Diego is providing daily updates of the Keeling Curve, the record of atmospheric CO2 measured at Hawaii’s Mauna Loa. These iconic measurements, begun by Charles David (Dave) Keeling, a world-leading authority on atmospheric greenhouse gas accumulation and Scripps climate science pioneer, comprise the longest continuous record of CO2 in the world, starting from 316 ppm in March 1958 and approaching 400 ppm today with a familiar saw-tooth pattern. For the past 800,000 years, CO2 levels never exceeded 300 parts per million.

The Hawaiian Islands ecoregion includes one of the world's wettest places, the slopes of Mount Wai?ale?ale, which average 460 in (12,000 mm) of rainfall per year. However, almost imperceptibly, rainfall over the Hawaiian Islands has been declining since 1978, and this trend is likely to continue with global warming through the end of this century, according to a team of scientists at the University of Hawaii at Manoa (UHM) and the University of Colorado at Boulder. This latest Hawaii rainfall study, published in the March 13, 2013, early online issue of the Journal of Geophysical Research, supports previous work conducted at the University of Hawaii.