Several Valley industries are included in the annual greenhouse gas report from the U.S. Environmental Protection Agency. The EPA classifies gases that trap heat in the atmosphere as greenhouse gases.

The fourth year of Greenhouse Gas Reporting Program data details greenhouse gas pollution trends and emissions broken down by industrial sector, geographic region and individual facilities.

In 2013, reported emissions from large industrial facilities in the U.S. were 20 million metric tons higher than the prior year, or 0.6 percent, driven largely by an increase in coal use for power generation.

Here in the Valley last year, plants related to the steel industry were among the leading producers of carbon dioxide (CO2), which makes up 82% of the greenhouse gases in the U.S.

The rapidly expanding Vallourec plant which straddles Mahoning and Trumbull Counties, produced 183,225 metric tons of CO2 in 2013. The ArcelorMittal Warren plant, which produces coking coal for steel making, emitted 182,311 metric tons of carbon dioxide last year, which was down fractionally from 2012 emissions at the plant.

Traditional coal fired energy producers also contributed their share of greenhouse gases. The Niles power plant operated by NRG recorded 978 metric tons of CO2 last year, which was far below the 453,826 tons emitted three years before.

Youngstown Thermal, which provides steam heat and cooling to several downtown buildings, recorded 52 metric tons of carbon dioxide in 2013. According to the Youngstown Thermal website, the company has been using more scrap wood to fire its boilers in an effort to reduce the use of coal.

Waste disposal facilities in the Valley produce a relatively large amount of CO2. The WTI Heritage hazardous waste incinerator in East Liverpool recorded 1,912 metric tons of the gas last year.

Local landfills far surpassed WTI in CO2 emissions. The Central Waste Landfill in Smith Township, Mahoning County reported 149,849 metric tons. The Mahoning Landfill in New Springfield emitted 52,676 tons, for a total of more than 202,000 tons from both landfills combined.

The General Motors Lordstown Complex East also has a place on the EPA interactive greenhouse gas map. The facility gave off 3,722 metric tons of CO2 last year. However the figure is far below the 72,084 tons emitted just two years earlier.

In 2013, GM embarked on a project to replacing existing lights at the stamping plant in Lordstown with 1,246 lower wattage, LED solid-state lighting fixtures. GM expected energy consumption to be reduced by 84 percent, with a CO2 reduction of about 8,500 metric tons.

The Greenhouse Gas Reporting Program is the only program that collects facility-level greenhouse gas data from major industrial sources across the United States, including power plants, oil and gas production and refining, iron and steel mills and landfills. The program also collects data on the increasing production and consumption of hydro fluorocarbons (HFCs) predominantly used in refrigeration and air conditioning.

More than 8,000 large-emitters reported direct greenhouse gas emissions to the program in 2013, representing approximately 50 percent of total U.S. emissions.

The data from these facilities show that in 2013 power plants remained the largest source of U.S. greenhouse gas emissions, with over 1,550 facilities emitting over 2 billion metric tons of carbon dioxide, roughly 32 percent of total U.S. greenhouse gas pollution. Power plant emissions have declined by 9.8 percent since 2010, but there was an uptick in emissions of 13 million metric tons in 2013 due to an increased use of coal.

According to the EPA, petroleum and natural gas systems were the second largest stationary source, reporting 224 million metric tons of greenhouse gas emissions, a decrease of 1 percent from the previous year.

Reported methane emissions from petroleum and natural gas systems sector have decreased by 12 percent since 2011, with the largest reductions coming from hydraulically fractured natural gas wells, which have decreased by 73 percent during that period. EPA expects to see further emission reductions as the agency's 2012 standards for the oil and gas industry become fully implemented.

Refineries were the third largest stationary source, reporting 177 million metric tons of greenhouse gas emissions, up 1.6 percent from the previous year.

Under President Obama's Climate Action Plan, EPA is taking steps to address carbon pollution from the power and transportation sectors, and to improve energy efficiency in homes, businesses and factories. Under EPA's proposed Clean Power Plan, carbon emissions from the power sector would decrease by 30 percent below 2005 levels and electricity bills would shrink by 8 percent by 2030.

An interactive map, key facts and figures from the Greenhouse Gas Reporting Program can be found by clicking this link