Human activities enhance Greenhouse Gas effects. The increasing Greenhouse gases are causing and accelerating climate change and global warming. The food industry and its wastage are one primary contributor to emissions. Yet, it is often ignored.
By Sida Lai in Week 8
Global climate change has already developed noticeable impacts on the planet’s environment. Glaciers have shrunk. The average land and ocean temperature increase has been 0.18°C per decade since 1981. And these changes will continue to occur throughout the century and beyond. NASA predicts more frequent wildfires, more extended periods of drought, and more intense tropical storms in the near future.
But what is climate change, and who is responsible?
In his book, “Climate Change: What Everyone Needs to Know,” the author Joe Romm from the Massachusetts Institute of Technology provides a systematic review of the phenomenon. In short, the human-made increase of greenhouse gases (GHG) causes and accelerates global warming and climate change through enhanced GHG effects in recent decades.
What is the Greenhouse Gas Effect?
The Sun emits energy to the Earth through short-wave radiation like Ultraviolet and visible light. About 30 percent of the radiation is reflected by the atmosphere, particularly the Ozone layer. But the rest is absorbed by the Earth. The First Law of Thermodynamics states the energy can not be created nor destroyed but act as a budget that needs balance. Hence, the Earth also releases the thermal energy from the Sun to reach the balance, frequently through long-wave radiation, infrared.
GHG effect occurs when the outgoing energy fails to escape the Earth but becomes trapped by GHGs in the atmosphere. They later heat the planet. “GHGs are gases that absorb the energy,” said Yarrow Axford, a planetary science professor from Northwestern University. “They include Carbon dioxide (CO2), methane (CH4), and Nitrous Oxide (N2O).”
Before the industrial revolution, GHGs’ natural presence reached an almost perfect balance of radiation and irradiation. They warmed the Earth while allowing substantial heat to escape, maintaining an appropriate climate. However, studies indicate human activities disrupt this balance by contributing to a significant increase of GHGs in the atmosphere. Hence, they enhance the GHG effect particularly in recent decades. These rising GHGs trap excessive energy that should originally be released into space, and thus heat the Earth’s surface more than ever.
How are Humans Increasing GHGs?
Industrial Revolution utterly alters the ways humans consume energy. In recent decades, human activities’ impacts on GHG emissions become more appalling. Researchers indicate CO2 is the primary GHG produced by human activities, notably the burning of fossil fuels. The inventions and widespread use of automobiles and airplanes drastically increased the need for oil. Agriculture practices and decaying organic wastes also contribute to the growth of CH4 and N2O. Romm highlights other indirect human effects on GHG increase. Deforestation from urbanization and industries contributed roughly 17% of the emission.
What is the Impact of Human Food on GHG Increase?
GHGs are generated throughout the food process from production to consumption. Researchers indicate that one-quarter (25 percent) of the world’s GHG emissions come from the food sector. This includes agriculture, livestock, manufacturing, packaging, storing, transportation, and cooking. The problem is more serious when it involves imports and exports. International transport and cold storage extend the emissions.
Food wastage is yet another severe but often neglected factor. 30 percent of food is wasted in the global supply chain. And so are the resources consumed and pollution emitted in the production process. Studies indicate if wastage is avoided, the World’s GHGs emissions could be reduced by eight percent.
But more serious issues occur in the waste handling phase. Food, when decaying in an environment that lacks oxygen, like landfills, produces CH4. And CH4 is 30 times stronger than CO2 in storing heat. Research indicates landfills account for 34 percent of all methane emissions in the U.S.
There are solutions, however. Composting, biodegrading waste into organic fertilizers, could be done with simple installed equipment at home or collectively. It is a way to recycle used energy naturally. The CH4 produced in the process could also be obtained and turned into electricity. Studies indicate if the strategy is employed universally, landfills’ emissions can be eliminated by 2.3 billion tons in 30 years.
Climate change and global warming from the enhanced GHG effect threaten humanity and the Earth’s livelihood. It is a clear result of the human-made weather effects since the industrial revolution and particularly in the past decades.
Tackling climate change is hard. But among many, the food sector could be a promising breaking-ground.