Summer is here, and the return of scorching sunshine, suffocating humidity and high-ozone-warning days to the Atlanta area — not to mention the official start of the hurricane season and the attendant media coverage — has had me thinking a fair amount about global warming in recent days. The subject also has been on the mind of the waste industry.

The National Solid Wastes Management Association (NSWMA), Washington, recently issued a white paper detailing how much the industry has reduced its greenhouse gas emissions over the past 30 years. Greenhouse gases — such as carbon dioxide and methane — trap heat once they are released into the atmosphere. (The report can be found by visiting and clicking on the “Research Bulletin” link.)

In 1970, net greenhouse gas emissions from municipal solid waste (MSW) activities totaled 60.5 million metric tons of carbon dioxide equivalents (MMTCO2E), the white paper says. By 2003, the figure had declined to 7.8 MMTCO2E. The emission reduction has occurred even as the amount of MSW has nearly doubled in the same time frame.

The report attributes the reduction to several factors. First, the industry has increased its collection and control of landfill gas through Subtitle D landfills. Also, recycling and composting have diverted materials that would otherwise have ended up in landfills. Finally, the increased use of waste to produce energy has avoided “emissions from combustion of fossil fuel to produce the equivalent amount of electricity,” the report says.

If the industry had not made the technological and operational improvements that it has in the past three decades, net greenhouse gas emissions from MSW operations would have totaled about 124.5 MMTCO2E in 2003, according to the report.

The report goes on to describe the ways in which the solid waste industry continues to curb its greenhouse gas emissions. Among the initiatives: using bioreactor landfills, the continued exploration of vehicles that run on alternative fuels such as compressed natural gas and liquefied natural gas, and using compost as landfill cover.

Considering the lack of a concentrated federal effort to address climate change, it is incumbent upon the states, local governments and the private sector to tackle the issue head on. As the NSWMA report shows, the solid waste industry has made commendable strides in the past 30 years. But now is not the time to let up. Waste firms and sanitation departments have an important role to play.

Hopefully, when it comes to curbing greenhouse gas emissions, the waste sector is just warming up.

The author is the editor of Waste Age