A Second Warning – Forcing Earth’s Ecosystems Beyond Their Breaking Point

The Athabaska glacier in the Columbia Icefields, Alberta, Canada, has receded 1.5 km and lost over 50% of its volume during the last 125 years (Photo: D. Hanneman)

Twenty-five years after the Union of Concerned Scientists and over 1700 independent scientists published their “World Scientists’ Warning to Humanity”, a new group of scientists (bolstered by 15,364 scientist signatories from 184 countries) have again issued a warning that humanity has not made significant progress in mitigating environmental challenges.

The recently published viewpoint of these scientists and signatories appears in the 11/13/17 issue of BioScience and can be read on line at “World Scientists’ Warning to Humanity: A Second Notice”. The authors review the 1992 warning of major environmental challenges and our response to it by:

we look back at their warning
and evaluate the human response
by exploring available time-series
data. Since 1992, with the exception
of stabilizing the stratospheric ozone
layer, humanity has failed to make
sufficient progress in generally solving
these foreseen environmental challenges,
and alarmingly, most of them
are getting far worse…

The newly published warning of our need to deal with these major challenges –  catastrophic climate change, deforestation, agricultural production associated with farming ruminants for meat consumption, and a sixth mass extinction event (just to name a few of them) – makes the reading of this viewpoint critical. It takes less than 10 minutes to read this, and – if you are a scientist, then sign on to support it. More than signing, find a way to become active in really dealing with these challenges.

Natural Gas and Climate Change

The rise in natural gas production, particularly in the U.S., has unquestionably impacted the global energy equation. Fueled by the unconventional-natural-gas revolution, natural gas is now a significant factor in the U.S. and global energy mix. As Sonal Patel summarized from the International Energy Agency’s (IEA) 2013 World Energy Outlook (WEO-2013):

By 2035, natural gas demand will outpace that of any other individual fuel and end up nearly 50% higher than in 2011. Demand for gas will come mostly from the Middle East—driven by new power generation—but also from Asian countries, including China, India, and Indonesia, and Latin America. Power generation continues to be the largest source of gas demand, accounting for around 40% of global demand over the period. New gas plants, meanwhile, are expected to make up around a quarter (or 1,000 GW) of net capacity additions in the world’s power sector through 2035.

Given the seemingly inevitable scenario of natural gas playing a significant role in the energy mix (and particularly in U.S., given the recent unconventional-natural-gas boom), how will its increased use influence climate change and future energy policies? The tenet that natural gas, being a cleaner-burning fuel, will lessen a carbon footprint has been bandied around for awhile now. Amy Harder, from National Journal, picks up this thread with:

First the aforementioned wisdom: Natural gas is unquestionably helping the United States reduce its climate footprint. Our nation’s greenhouse-gas emissions have dropped to levels not seen since the 1990s, thanks in part to this cleaner-burning fuel. Natural gas produces half the carbon emissions of coal and about a third fewer than oil. This is why everyone in the Obama administration, including the president himself, can’t talk enough about the climate benefits of natural gas.

Three disparate factors make the relationship between natural gas and climate change not so unequivocally simple and good. Concerns about methane emissions persist, but notwithstanding that challenge, two greater problems loom: First, shifting significantly away from coal to natural gas doesn’t get the planet anywhere close to the carbon-reduction levels scientists say we must reach. And second, while the natural-gas boom is great for the economy and the immediate reduction of greenhouse-gas emissions, it has deflated the political urgency to cut fossil-fuel dependence, which was more compelling when we thought our resources of oil and natural gas were scarce. We have a great problem of energy abundance.

Obviously, natural gas is not the total panacea for “fueling” the transition to a carbon-negative energy mix. But given the current and predicted production/market conditions, it will be a considerable part of the future global energy equation.

Rising Seas and Carbon Footprint Visualizations

National Geographic "Rising Seas" map of projected North American shoreline change from ice melt. Map from: http://tiny.cc/xc0z9w
National Geographic “Rising Seas” map of projected North American shoreline change from ice melt. Map from: http://tiny.cc/xc0z9w

New sets of interactive maps help to visualize both the impact of rising seas on the world’s coastlines and U.S household carbon footprints.National Geographic has posted a set of world-wide interactive maps that show new coastal outlines resulting from the premise of all ice melting and thus raising sea level approximately 216 feet. As noted by the authors:

There are more than five million cubic miles of ice on Earth, and some scientists say it would take more than 5,000 years to melt it all. If we continue adding carbon to the atmosphere, we’ll very likely create an ice-free planet, with an average temperature of perhaps 80 degrees Fahrenheit instead of the current 58.

Continuing on the topic of adding carbon to the atmosphere, University of Berkeley researchers, Christopher Jones and Daniel Kammen, looked at the spatial distribution of U.S. household carbon footprints. The researchers first point out the obvious in that carbon footprints in densely populated areas are typically low because of smaller residences, shorter commutes, and the availability of mass transit. Here’s the catch though – the suburbs have an unusually large carbon footprint. In fact the footprint is so large that it negates the “green” urban core. As Jones and Kammen summarize:

As a policy measure to reduce GHG emissions, increasing population density appears to have severe limitations and unexpected trade-offs. In suburbs, we find more population- dense suburbs actually have noticeably higher HCF, largely because of income effects. Population density does correlate with lower HCF when controlling for income and household size; however, in practice population density measures may have little control over income of residents. Increasing rents would also likely further contribute to pressures to suburbanize the suburbs, leading to a possible net increase in emissions. As a policy measure for urban cores, any such strategy should consider the larger impact on surrounding areas, not just the residents of population dense communities themselves. The relationship is also log−linear, with a 10-fold increase in population density yielding only a 25% decrease in HCF. Generally, we find no evidence for net GHG benefits of population density in urban cores or suburbs when considering effects on entire metropolitan areas.

U.S. Average Annual Household Carbon Footprint by Household. "Source: UC Berkeley CoolClimate Network, Average Annual Household Carbon Footprint (2013)"
U.S. Average Annual Household Carbon Footprint by Household. “Source: UC Berkeley CoolClimate Network, Average Annual Household Carbon Footprint (2013)”