Human Responses to Enhanced GHGs

The Nature and Extent of Climate Change

Since the Industrial Revolution, a significant amount of GHGs has been added into the atmosphere, largely by burning fossil fuels to generate electricity, heat and cool buildings, and power vehicles — as well as by clearing forests. The lion’s share of enhanced GHGs being added to the atmosphere are carbon dioxide, methane, nitrous oxide, and fluorinated gases. When these gases are emitted into the atmosphere, many remain there for long time periods, ranging from a decade to thousands of years. While past emissions affect our atmosphere in the present day, current and future emissions will continue to increase the levels of these gases in the atmosphere for the foreseeable future. (U.S. Environmental Protection Agency [EPA], 2016)

Common and Stagl (2005) emphasize that what is changing the climate is the enhanced greenhouse effect. GHGs, they explain, trap heat (the energy of the sun) like a greenhouse in the lower part of the atmosphere. As more of these gases are added to the atmosphere, more heat is trapped. This extra heat leads to higher air temperatures near the Earth’s surface, changes weather patterns, and raises the temperature of the oceans. The estimation of all aspects of climate change is a complex and daunting task. One reason behind such complexity, as clarified by Henderson et al. (2018), is the presence of positive feedback loops. For instance, global warming reduces the amount of snow and ice on the Earth’s surface. Since snow and ice reflect more sunlight back into space, compared to exposed land, this reduction further accelerates the rate of global warming.

The Impacts of Climate Change

People and the environment are tremendously affected by the changes in weather patterns and global warming. Sea levels are rising, glaciers are melting, and plant and animal life cycles are changing. These types of changes can cause fundamental disruptions in ecosystems; thereby affecting plant and animal populations, communities, and biodiversity. Such changes can also affect people’s health and quality of life, including where they can live, what kinds of crops are most viable, what kinds of businesses can thrive in certain areas, and the condition of buildings and infrastructure. Some of these changes may be beneficial to the people of certain regions. Over time, however, many more of these changes have negative consequences for people and society. (EPA, 2016)

Climate change can directly impact human health and well-being; e.g., due to heat stress, increased floods and storms. Its indirect effects can also be transmitted via impacting other plants and animals; resulting in agricultural productivity reduction or biodiversity loss, as examples.

The threat of climate change is one of the biggest issues facing the world. According to Heal (2017), the scientific community has reached a consensus on that, due to the human emissions of greenhouse gases, the Earth is warming and the consequences of continued warming are expected to be severe. Outside academia, nonetheless, there is widespread disagreement; not only on the issue, but also on how to respond to it. Some people and politicians, known as climate deniers, totally reject the role of humans in global warming. Those who accept it, look at the issue from different perspectives. Some business leaders, for example, see the viability of their firms in jeopardy as a direct consequence of climate change. Others, in contrast, consider it as an opportunity to run their lucrative businesses by promoting technologies that help communities mitigate the risks of climate change and adapt to its effects. (Henderson et al., 2018)

Responding to the Climate Problem

Three types of human responses to the enhanced GHGs are distinguishable: adaptation, offsetting, and mitigation. Adaptation simply means adjusting climate change; as examples, by building defensive walls against floods, limiting construction in flood-plain areas, or using new strains of crops to cope with higher temperatures (Common and Stagl, 2005). Offsetting is the intentional interfering of humans in the climate system; for instance, by injecting sulfates into the atmosphere to use their high reflectivity to stop part of the sun’s radiation from reaching the Earth’s surface (Henderson et al., 2018). Mitigation involves either reducing the amount of GHGs released into the atmosphere, or enhancing the operation of the natural sinks for the gases (Common and Stagl, 2005).

Reduction of GHGs, in its turn, includes one of the three following actions (Henderson et al., 2018):

·?????? moving away from fossil fuels,

·?????? improvement in energy efficiency, and

·?????? changes in land use (e.g., agricultural, and forestry).

World Economic Forum’s (2018) “The Global Risks Report” identifies failure of climate change mitigation and adaptation as one of the top five global risks, in terms of both likelihood and impact. On the verge of the climate tipping point, humans have no choice but to organize their economic activity more thoughtfully so that economic progress and conservation of the natural world can go together (Heal, 2017). Carbon pricing approaches (market mechanisms such as carbon taxes and cap-and-trade regimes) are, in fact, economic tools that economists hope could help us move away from burning fossil fuels. They are intended to mitigate the consequences of global warming before it becomes too late.

Addressing climate change, the greatest external effect in human history in Heal’s (2017) terms, is a complex issue as it involves at least three difficult problems (Henderson et al., 2018): discount rates, free riding, and global geopolitics. Given the fact that the benefits of addressing enhanced GHG emissions almost certainly outweigh the costs – and that the effects of increased emissions remain in the atmosphere for so long and affect the welfare of future generations – still a concerted global action to solve the problem is not easy. Who should pay for responses to climate change, and how much should be spent are the matters of ongoing debate. Despite the ongoing debate on these issues, the international community has agreed upon so far that shaping behavior through market mechanisms are the most effective ways to reduce GHG emissions. Kyoto Protocol, adopted in 1997 and taking effect in 2005, was the first attempt to implement a global cap and trade system.