A large crowd gathered today in Plymouth, England, to extend best wishes to one of the world's most famous climate activists.
Greta Thunberg, a 16-year-old Swedish student, has decided to cross the North Atlantic on the Malizia II, a solar-powered racing yacht.
She refuses to fly to set an example to others about how to reduce their carbon footprint.
So the ocean voyage was deemed to be the best way for her to reach New York City to attend a climate conference.
It's possible to follow her journey on the windy.com website.
Thunberg's departure from Plymouth came on the same day that a Cornell University professor published a paper suggesting that fracking for natural gas is a "major driver" of a recent increase in global atmospheric methane.
“This recent increase in methane in massive,” Robert W. Howarth told the Cornell Chronicle. “It’s globally significant. It’s contributed to some of the increase in global warming we’ve seen and shale gas is a major player.
“If we can stop pouring methane into the atmosphere, it will dissipate,” he said. “It goes away pretty quickly, compared to carbon dioxide. It’s the low-hanging fruit to slow global warming.”
In the journal Biogeosciences, Howarth wrote "that shale-gas production in North America over the past decade may have contributed more than half of all of the increased emissions from fossil fuels globally and approximately one-third of the total increased emissions from all sources globally over the past decade."
Professor contradicts politicians' claims
British Columbia is one jurisdiction that has encouraged fracking of natural gas.
And both the federal and provincial governments are backing the $40-billion LNG Canada project near Kitimat, which will rely on fracked gas.
Some politicians in Canada have described natural gas as a bridge fuel to a cleaner future because it will replace use of coal in Asia.
But Howarth rejects that claim.
"In October 2018, the Intergovernmental Panel on Climate Change issued a special report, responding to the call of the United Nations COP21 negotiations to keep the planet well below 2 ∘C of the pre-industrial baseline (IPCC, 2018)," he wrote in the paper. "They noted the need to reduce both carbon dioxide and methane emissions, and they recognized that the climate system responds more quickly to methane: reducing methane emissions offers one of the best routes for immediately slowing the rate of global warming (Shindell et al., 2012).
"Given our finding that natural gas (both shale gas and conventional gas) is responsible for much of the recent increases in methane emissions, we suggest that the best strategy is to move as quickly as possible away from natural gas, reducing both carbon dioxide and methane emissions," he continued. "Natural gas is not a bridge fuel."
According to Howarth, two-thirds of all the new natural gas produced in the world over the past decade occurred in the United States and Canada.
Howarth pointed out that in his paper while methane emissions from fracking are often described as "leaks", this isn't always the case.
In fact, he wrote, some releases of methane result from "purposeful venting, including the release of gas during the flowback period immediately following hydraulic fracturing".
Other deliberate releases of methane can come in the "rapid release of gas from blowdowns during emergencies", "for routine maintenance on pipelines and compressor stations", and "the steadier but more subtle release of gas from storage tanks", according to Howarth.
"Do large capital investments for rebuilding natural gas infrastructure make economic sense, or would it be better to move towards phasing natural gas out as an energy source and instead invest in a 21st-century energy infrastructure that embraces renewable energy and much more efficient heat and transportation through electrification (Jacobson et al., 2013)?" Howarth wrote in his paper.
He also pointed out that methane emissions contribute to higher levels of ground-level ozone, also known as smog.
That comes with a cost to public health and agriculture.
"Based on the social cost of methane emissions of USD 2700 to USD 6000 per ton (Shindell, 2015), our baseline estimate for increased emissions from shale gas of 9.4 Tg per year corresponds to damage to public health, agriculture, and the climate of USD 25 billion to USD 55 billion per year for each of the past several years," Howarth maintained. "This is comparable to the wholesale value for this shale gas over these years."