Climate Change, Economy / Finance, energy, Environment, Sustainable Development

You Can’t Sit Out Climate Change

May 13 2019

By William Mebane

The writer is former Director of Energy Efficiency Department at ENEA, the Italian National Agency for New Technologies, Energy and Sustainable Economic Development

In 2007 a MIT survey revealed that nearly 60% of Americans feel that “until we are sure that global warming is really a problem, we should not take any steps that would have economic costs” or “its effects will be gradual so we can deal with the problem gradually”(Sherman, 2007).  Now following a decade of devastating hurricanes in the U.S., record droughts in Cape Town and other areas, and even forest fires in the Arctic, more citizens are sensitive to the issue but with cost concerns and a muted sense of urgency. “Three-quarters of Americans express concern that efforts to address the issue will raise prices on things they buy and just two in 10 are very confident that those efforts, in fact, would reduce global warming. The latter, in particular, contributes to an absence of broad urgency on the issue. Just a narrow majority, 53 percent, favors immediate action over more study. And many of those who back some policies think they should be voluntary, not mandated.” (Langer 2018).

This cautious wait and see attitude would be reasonable if the climate dynamics, and related economics, were linear; but both are not.

“The long-term historical record indicates that after some forcing event starts the warming process, amplifying feedbacks in the climate systems reinforce that warming, which causes the warming to speed up. The paleoclimate record suggests that the initial forcing could be a release of greenhouse gases or a change in Earth’s orbit that brings more intense sunshine to parts of the planet. One important amplifying feedback occurs because, as the planet warms, the extent of both sea ice and land-based ice (glaciers) shrinks. Thus, white ice, which is very reflective, is replaced by the blue sea or dark land, each of which absorbs much more solar radiation. Another key rapidly acting amplifying feedback is driven by water vapor. As the planet starts to heat up, evaporation increases, which puts more water vapor into the air. Water vapor is a potent heat-trapping greenhouse gas. Thus, an increase in water vapor causes a very long increase in warming, which causes an increase in water vapor and so on.” (Romm 2018).

The total amount of CO2 is building up and the longer we wait, the more we will have to remove to get back to reasonable non-threatening levels, estimated at more than an 80% drop in emissions under many scenarios.

Thus we are accelerating towards possible disaster. Already we are experiencing global temperatures that are increasing 50 times faster than it did during preindustrial times; oceans are becoming more acidic today, due to dissolving CO2, at ten times faster than the rate 55 million years ago when a mass extinction of marine species occurred; and from 1979 to 2012 late summer Arctic ice volume has dropped by 80%. Climate warming is causing extreme weather events to become more frequent, creating a new normal. Storms that were previously 100-year storms are becoming 10-year storms. “Because climate change is expected to make dry or semiarid regions hotter and drier, we would expect longer and more intense droughts in such regions, such as the Mediterranean and U.S. Southwest. Eventually, the climate is projected to change so much that the regions normal climate becomes a drought.” (Romm 2018).

“Total anthropogenic GHG emissions have continued to increase over 1970 to 2010, with the highest in human history from 2000 to 2010. CO2 emissions from fossil fuel combustion and industrial processes contributed to about 78% of the total GHG emission increase from 1970 to 2010.” (IPCC, 2018).

Also, “Humans are transforming Earth’s natural landscapes so dramatically that as many as one million plant and animal species are now at risk of extinction, posing a dire threat to ecosystems that people all over the world depend on for their survival, a sweeping new United Nations assessment has concluded. With the human population passing 7 billion, activities like farming, logging, poaching, fishing and mining are altering the natural world at a rate ‘unprecedented’ in human history. At the same time, a new threat has emerged: Global warming has become a major driver of wildlife decline, the assessment found, by shifting or shrinking the local climates that many mammals, birds, insects, fish and plants evolved to survive in”. (Plumer 2019)

The world’s leading climate scientists have warned there is only a dozen years for global warming to be kept to a maximum of 1.5 degree C., beyond which even half a degree will significantly worsen the risks of drought, floods, extreme heat and poverty for hundreds of millions of people. (Watts, 2018)

The good news is that the cost of keeping the climate at a sustainable level of about 450 ppm CO2 equivalent by 2100 is not prohibitive if we act now. The latest IPPC report indicates that losses in global consumption (due to increases in investments) are on the average 1.7% in 2030, 3.4% in 2050 and 4.8% in 2100.

Naturally, these substantial reductions in emissions will require a significant change in investment patterns. “Over the next two decades (2010-2029) the annual investment in conventional fossil fuel technologies is projected to decline by about 30 billion USD (-20% compared to 2010) while annual investment in low carbon electricity supply is expected to rise by about 147 billion USD (100% compared to 2010. For comparison, global total annual investment in the energy system is presently about 1200 billion USD. In addition, annual incremental energy efficiency investments in transport, buildings and industry are projected to increase by about 336 billion USD.

However, we must act now, specifically during the 2019-2030 period, to bring down annual CO2 emissions to between 30 to 50 Gt CO2 equivalent in 2030. The above estimates are based on this alert action response. If the world does not achieve this, we will be emitting more and it will cost more to clean up. If by 2030 we have annual emissions exceeding 55 Gt CO2 eq., the average additional costs are 44% in 2030-2050 and 32% in 2050-2100 to maintain a 2100 concentration level of 450 to 550 ppm CO2 eq. (IPPC, 2018)

It pays to act as fast as possible to counter the accelerating dynamics of climate change. Keep in mind that economists can more easily estimate abatement costs because we have begun these types of investment and there are no estimates of the multiple benefits of avoiding climate damage in the IPCC calculations. They have preferred to be prudent and non-controversial. If we examine one of the higher emission scenarios, say 720 to 1000 ppm CO2 eq. in 2100, the cumulative emissions (2011- 2100) are estimated as 3620 to 4990 Gt CO2 eq., roughly five times the cumulative emissions of the fast start scenario. What is the benefit of avoiding all the costs of the damage at these levels and what would be the cost of bringing down such extra emissions?

What can we do now? As individuals we may install solar panels on our homes; apply energy efficiency in our houses and buildings with a good return on investment, learn to eat meat much less, be efficient in travel using public transport, railways, even bicycles, own or share an energy efficient or electric car. Set an example for your family and neighborhood, teach the fundamentals of climate action to the kids. Change your purchasing habits to favor environmentally sustainable goods and services.

The challenge is daunting, and since it is in our best interest to move fast, there is no single magic bullet – we have to use all of our tools (also different combinations in different states and regions): carbon taxes (revenue neutral), regulations for energy standards, cap and trade, incentives for electric cars, solar energy production, energy savings and more.

The silver lining is that this creates multiple opportunities for business and jobs: with energy efficiency investments in buildings, transport and industry; solar energy production facilities in all its forms and local distribution systems; the reinvention of goods that are natural and recyclable; and sustainable agriculture. Why would the U.S. want to be out of this revolution?



IPCC 2018, Global Warming of 1.5 C Degree, Summary for Policy Makers, October 6, 2018 in particular pages 12-15 and 25-27.


Langer, G. 2018, “Public Backs Action on Global Warming – but with Cost Concerns and Muted Urgency,” (ABC News, Stanford University, Resources for the Future Poll: Public Attitudes on Global Warming), ABC News July 16, 2018

Plumer, B. 2019, “Humans Are Speeding Extinction and Altering the Natural World at an Unprecedented Pace”, New York Times, May 6, 2019

Romm, J. 2018, Climate Change: What Everyone Needs to Know, Second Edition 2018,

Sherman, J. D. and Sweeney, L. B. 2007, Climate Change (2007) 80: 213-238.

Watts, J. 2018, The Guardian, October 8, 2018

site admin