It's really very simple. If we don't eliminate or slow the emission of greenhouse gases into our atmosphere, Hawai'i and the rest of the world will deteriorate dramatically within a generation.

Last month, the United Nations Intergovernmental Panel on Climate Change released a report that confirmed what many of us feared: The existence of global warming is unequivocal and human activity is almost certainly responsible.

Many of the catastrophic predictions are to take place a thousand years from now; however, we are suffering under the effects of global warming today.

One of the most pressing environmental issues facing Hawai'i is the rise in sea level. The Pacific Ocean rose 6 to 8 inches in the 20th century, and scientists are now predicting an additional rise of 17 to 25 inches, meaning inundation of low-lying areas. Flooding will dramatically affect Hawai'i's main industry, tourism, which operates at sea level throughout much of our state.

Sea-level change also threatens Hawai'i's hundreds of endangered species. We need look no further than Whale-Skate Island in French Frigate Shoals to see the destructive effects of sea-level rise and erosion. Once a large refuge and nesting area for seals, turtles and birds, the island has shrunk to the point where it is submerged. Scientists predict that two-thirds of some of the low-lying Northwestern Hawaiian Islands will meet the same fate.

Rising temperatures could also mean extinction for species living at high altitudes on Mauna Kea. One example is the wekiu bug, which depends on snowfall to capture its food, but whose existence is threatened by fewer snowfalls each year. By the end of the century, Hawai'i's delicate ecosystem will be dramatically altered by global warming, meaning we could lose these precious native creatures forever.

Rising oceans also will mean accelerated erosion of beaches and the destruction of coastal wetlands because of increased salinity and saltwater contamination of drinking water. Erosion and saltwater infiltration have affected taro and other crops growing in low-lying areas.

The National Oceanic and Atmospheric Administration recently reported that 2006 was the hottest year on record for the United States. The past 10 years were among the 25 warmest ever recorded for the United States. In Honolulu, the average temperature increased 4.4 degrees over the past century, and that rate is expected to accelerate.

Frequent droughts are another concern. Droughts not only hamper agricultural production, but also exacerbate the spread of water-borne diseases by wiping out supplies of fresh drinking water. Increased evaporation and changes in rainfall will affect runoff and water availability. Frequent heat waves hold grave consequences for our children's health, not to mention that of our elderly population. We can also expect more frequent and intense storms and hurricanes, already a concern for us here in the Islands.

Although the IPCC report forecasted some dire predictions for the years ahead, there was also a ray of hope: There are steps we can take now to thwart this crisis and alleviate the damage of global warming. It is crucial that we do our part in Hawai'i.

The burning of fossil fuels — coal, oil and natural gas — takes a heavy toll by releasing large amounts of greenhouse gases into the atmosphere. We can begin today by taking a more proactive stance on limiting these harmful gases.

With this goal in mind, the House Committee on Energy and Environmental Protection has passed out two important bills. House Bill 226, introduced by Rep. Josh Green, requires the Department of Business & Economic Development and the Department of Health to submit a comprehensive clean-air plan to the Legislature in time for the 2009 session. The ultimate goal is to reduce statewide greenhouse gas emissions to below-1990 levels as suggested in the Kyoto Protocol, and eventually, to lower emission levels to the lowest per-capita amount in the nation.

I proposed the second bill, HB 678, which requires DOH to report and verify greenhouse gas emissions in Hawai'i and to monitor and enforce compliance much like California has done, and very recently, Washington. The measure sets a goal to lower statewide emissions significantly by 2020. The Legislature intends for this program to place our state among the nation's leaders in our efforts to curb greenhouse gas emissions.

Both bills are advancing in the Legislature.

Environmentalist Bobby Kennedy Jr. has spoken about "pollution-based prosperity," which is how he views the current degradation of our environment. "Environmental injury is deficit spending," he has said. "It loads the cost of our generation's prosperity onto the backs of our children." For the sake of the next generation, let's bring these important discussions to the fore and take the steps to ensure a better future for the children of Hawai'i.

Rep. Blake Oshiro represents District 33, which includes Halawa, 'Aiea and Pearlridge. He wrote this commentary for The Advertiser.