WSB photojournalist Christopher Boffoli is back from covering this afternoon’s rally at Pier 66, outside the EPA’s public hearing on whether to designate climate change as a threat to human health. His first photo shows some of the youngest delegates from West Seattle’s CoolMom chapter to attend; the CoolMom kids spent some time up on stage, and other West Seattleites were there, including a delegation from Sustainable West Seattle. Here’s an overview of the rally:

Among the speakers, Mayor Nickels:

The hearing is scheduled to continue until at least 8 pm; here’s how to listen to live audio. ADDED 5:08 PM: From the mayor’s office, his “written testimony” submitted during the hearing:

“Seattle is a city blessed with natural beauty. You can see it in the sparkling waters of Elliott Bay and the snowy glaciers of the Cascade mountain range. This bounty has provided us with abundant, clean hydroelectric power, the best-tasting drinking water in the nation, and our iconic salmon and orca. All that is at risk from global warming.

The Environmental Protection Agency is now posing the question whether greenhouse gas emissions endanger us. As mayor of the city of Seattle, my answer is an emphatic ‘yes.’

The University of Washington’s Climate Impacts Group estimates that the average warming rate in the Pacific Northwest will be a half-degree per decade, or more than two-and-a-half times the rate experienced throughout the 20th century. This pace will significantly impact our ecological systems by mid-century. For our mountains, this change translates into a 38-46 percent reduction in annual snow-pack statewide by 2040. Such a dramatic change will disrupt our hydro-power system, which provides 70 percent of our region’s electricity. Simply put, we will face an energy crisis of historic proportions.

Ironically for a city known for its rain, global warming is predicted to bring even more precipitation for Seattle. Scientists predict that the duration and intensity of our storms will increase. We’ve already been experiencing this. In just the past five years, Seattle has suffered two 100-year rains. Our infrastructure was not built for this type of urban flooding. In December 2007, I watched as rivers of water crested over roadways and through Seattle neighborhoods. That month, the Chehalis River flood closed Interstate 5 for four days. Total cost of storm recovery amounted to more than $1 billion across the state. These events are endangering our communities.

As temperatures warm, polar ice caps melt and sea levels rise. As a coastal region, our businesses, residents and recreation spots are at risk of flooding and inundation. In Seattle, we have identified 700 to 1,000 acres of land at risk, including the South Park neighborhood and Harbor Island, a center of the maritime industry. We must take this threat seriously.

As more carbon is captured in our oceans, our marine waters become more acidic. Shellfish, coral and other species become vulnerable. Washington state’s $100 million shellfish industry is endangered by greenhouse gas emissions.

As the cold mountain run-off in spring and summer diminishes, our creeks and rivers become warmer. That’s deadly for salmon and other species that are dependent on fresh, cold water for survival. University of Washington scientists predict that by 2080, 35 percent of western Washington rivers will be too warm for salmon. This may push a northwest icon off the edge of extinction.

The city of Seattle uniquely benefits from our natural wonders, and it has much to lose, but it is also not alone. Cities across the country are harmed by the effects of global warming. New Orleans suffers from sea level rise and storm intensity. Phoenix suffers from intense summer heat and increases in heat-related mortality. Boston suffers from stress on its water and energy systems.

That’s why more than 940 mayors have signed the United States Conference of Mayors Climate Protection agreement. We know that global warming is endangering our cities. We know that we need a federal partner to help solve this global threat. Whether by regulation or by legislation, it is time for federal action to curtail greenhouse gas pollution and reduce the danger our residents face from global warming.

On behalf of the US Conference of Mayors, I am here to state emphatically that the effects of climate change endanger the health and welfare of our residents very directly. I urge the EPA to adopt your findings, and move forward in protecting our communities from the dangers of greenhouse gas emissions.”