The goal of tackling climate change should be to restore Earth’s atmosphere to pre-industrial levels of greenhouse gases such as carbon dioxide and methane, says top ecologist Rob Jackson, far exceeding the current target of controlling emissions to keep warming at or below 1.5oC.
Jackson, one of the top five most-cited environmental scientists in the world and chair of the Global Carbon Project (GCP), a leading scientific group tracking GHG emissions, in an Aug. 4 conference talk cited the “drumbeat of doom” on climate, including wildfires with record heat and drought, the Great Barrier Reef bleached white and dying, and a report documenting that global temperatures have already risen 1.1oC. He said, “we need a new narrative of hope” that can be provided by restoration, defined as bringing ecosystems that have been degraded, damaged, or destroyed back to their previous condition.
“Restoration must our goal for the atmosphere,” not just stabilizing temperature at 1.5oC, he said in his keynote speech, “Restoring the Atmosphere,” at the annual conference of the Ecological Society of America, a non-partisan non-profit professional society of scientists who promote ecological science. He added “normal people don’t relate to that” and restoration does not inspire action. By analogy, he noted that the Endangered Species Act does not stop at saving plants and animals from extinction but “mandates their recovery,” as must happen with the atmosphere. It can be done in a lifetime, he said.
Jackson -- a professor and senior fellow at Stanford University’s Woods Institute for the Environment and at the Precourt Institute for Energy -- acknowledged that aiming for a pre-industrial atmospheric condition is “a ridiculous suggestion.”
But the target is nevertheless “my dream,” he said, and described the diverse pathways that could contribute to the goal and why they must be taken.
Although ecology and natural solutions, such as reforestation, will play an important role in curbing GHGs, existing and new technologies will also be needed, Jackson said, including some technologies that ecologists like himself might personally not like.
He said the GCP’s 1,000-plus scientists across the globe estimate annual carbon emissions from land, ocean, industry, and agriculture and just released the group’s global methane budget in July, showing record methane emissions through 2017. In August, GCP will release its first-ever budget of sources and sinks for nitrous oxide, a “long-lived, potent, and neglected” GHG.
Discussing cumulative emissions allowable in a “carbon budget” to stay within 1.5oC, Jackson noted that during the 2008 recession emissions temporarily fell, but then “roared back.” Emissions have dropped significantly during the COVID-19 pandemic, but GHGs will rise again as “we cannot cut emissions by locking people in their homes” and they must return to work, he said.
Today, even with rapid growth in renewable power, GHG emissions are 61 percent higher than when the United Nations Intergovernmental Panel on Climate Change issued its first report in 1990. That is because demand for energy per person has meant “everything is going up,” including energy from wind, solar, and other renewables, coal, oil, gas, and nuclear. “We will shoot past 1.5oC” and then hurtle past 3oC “if we do not act quickly,” Jackson said.
But it is possible to support electric vehicles (EVs), or redesign cities to promote walking and biking, re-envision telecommuting to cut traffic congestion, using lessons being learned during the current pandemic. Significant GHG cuts could be achieved by targeting as much funding as possible through a green stimulus. From the $50 billion spent on clean energy in the Obama stimulus, Americans are reaping record low electricity prices; over 770,000 homes were weatherized, wind and solar doubled, and 688 square miles of land used for Cold War-era nuclear testing were cleaned up. But so far, of $12 trillion stimulus funds already spent by the world’s 50 biggest economies, only one-fifth of a percent, or 1/1,000, was for green priorities.
Jackson discussed the need for “negative emissions” strategies using natural climate solutions (NCS) while still meeting food, fiber, and biodiversity needs.
Some examples of NCS include reforestation, biochar in grassland soils, and coastal wetlands restoration. NCS can address many emissions, but “they won’t be enough on their own.” Soils can store carbon and provide co-benefits, he said, citing work by the International Soil Carbon Network. The global Bonn Challenge seeks to bring 150 million hectares of the world’s deforested and degraded land into restoration by 2020, and 350 million hectares by 2030. The Trillion Trees Initiative could help but also could pose problems because, for example, tree plantations use more water and can alter water and energy balance, cutting stream flow by about 50 percent, especially in drier, marginal habitats.
Generally, Jackson said, negative emissions are necessary because steep emission cuts are needed. But other measures will be needed. Scientists in Iceland are turning CO2 into seltzer water, then pumping it underground, where it turns it to stone. Carbon capture and storage is underway, and a carbon price is needed, he said.
Jackson emphasized methane emissions, warning “we need to guard against runaway methane” if permafrost melts, and noting that ruminant cows and other farm animals are a major methane source that could be tackled by eating less beef, drying manure, and other steps. Jackson and his colleagues are also working to measure natural gas leaks in cities, which are extensive from old cast iron gas pipes and other sources, as well as using satellite technologies to monitor massive leaks seen in California from landfills, dairies, and oil and gas facilities.
But Jackson said “we can and will” restore atmospheric methane to pre-industrial levels in his lifetime, though CO2 restoration will take longer. The world needs EVs coupled to clean energy, technologies to tackle industrial heating, a change in population growth and wealth inequality, and many other measures to make planetary health a priority, he said. -- David Clarke