The trends we are seeing in global climate (increased global temperature, sea level rise, etc.) are linked to the increase in greenhouse gasses (carbon dioxide, methane and nitrous oxide) in the atmosphere. There are now approximately 1.5x, 3x and 1.3x the amount of these gases in the atmosphere compared to 2,000 years ago. These gases are good at absorbing infra-red or thermal radiation (the one we can see with FLIR cameras), keeping in more of the heat that would normally be lost to space. Emissions of these gases are expressed in a common currency called carbon dioxide equivalent.

There are a number of sources that emit these gases into the atmosphere: natural and human-made or human-induced. In Canada, the top sources are from the energy and transportation sectors, with the agriculture sector contributing about 10%. These emissions are mostly in the form of non-carbon dioxide gases (i.e. methane and nitrous oxide). Methane is produced in the rumen of cows and then lost to the atmosphere when cows burp. Nitrous oxide is produced in the soils and is associated with the nitrogen cycle so that nitrogen fertilizers promote nitrous oxide emissions. There are a number of management practices that farmers already use or could use in the future to be part of climate solutions. These include improving feed use efficiency, using the 4R nutrient stewardship program for nitrogen fertilizer use and improving soil health through use of perennials.

– Dr. Claudia Wagner-Riddle, University of Guelph