California plans to install a network of computerized monitors to measure methane emissions from regions that are home to farms, dairies, landfills and other suspected methane sources.

It will be the first network of its kind in the United States and will help the state take steps toward reducing gas emissions related to global warming, say officials.

The plan is to place seven devices about the size of a personal computer in regions where methane emissions are believed to be the highest. Those include the farm fields of the Sacramento and San Joaquin valleys and landfills in the Los Angeles basin.

"What we'll be able to do is to find the identity, the location and the strength of methane emissions within the state," says Jorn Herner, the scientist managing the program at the California Air Resources Board. "This is new and pioneering work."

Picarro makes the methane measuring devices. California's air board spent about $400,000 on the devices and software modeling to analyze the data. The monitors are considered the most precise method scientists have to monitor methane and carbon dioxide in the atmosphere. The first data is expected to be available by summer 2011.

California's approach is the most extensive effort to gauge local emissions, say scientists. The information from the monitoring system will  inform state regulators who are charged with implementing the state's 2006 landmark global warming law. Known as AB32, the law requires the state to cut its greenhouse gas emissions by about 25 percent over the next 10 years.

The National Oceanic and Atmospheric Administration, NASA, academic research scientists and other countries have deployed similar monitors in the last two years to track greenhouse gases around the globe.

According to Pieter Tans, a senior scientist at NOAA's Earth System Research Laboratory in Boulder, Colo., information provided by the monitors should fill an information gap. "Even though we can measure global increases precisely, we cannot say what the causes are, so we need more local measurements for that," he says.

State regulators currently rely on power plants, oil refineries and others to report their own emissions. That information is used to compile California's greenhouse gas registries and will determine which polluters must buy emission permits under a state cap-and-trade system now being crafted.

The electronic monitors are designed to verify how much methane is in California's air. A more accurate accounting of emissions should build confidence in carbon-trading markets, says Michael Woelk, Picarro's chief executive.

Paul Bettner, manager of environmental affairs at the California Rice Commission, says farmers support any effort that bases regulatory decisions on good science. "If this contributes to them improving their understanding of all sources of methane, it's probably a good thing," Bettner said.

AP contributed to this article.

Source: Porkmag (sister publication to Dairy Herd Management)