Woodard et al. (2019) have calculated that climate change is sufficiently disruptive of the global economy that it will lower carbon dioxide output significantly going forward. In other words, no matter what we do about the Paris Climate Agreement, CO2 levels from burning fossil fuels are likely to fall. This might be viewed as good news…it ought to offset the existing high levels of CO2 in the atmosphere and at least stabilize things, never mind that the economy (and therefore, we) will suffer. Not so fast. The other thing that climate change is doing is heating up the oceans which reduces their ability to absorb CO2 from the atmosphere; this and other natural climate sinks are failing, so even with reduced human CO2 production, atmospheric levels are still going to rise. Plus the global economy is going to sink. This latter fact suggests that we’ll have fewer economic resources (money) to spend on adapting to the adverse effects of climate change. We know what these are: wealth inequality, crop failures, coastal flooding, etc.
I guess it’s bad news all around.
WoodardDL, DavisSJ, RandersonJT (2019) Economic carbon cycle feedbacks may offset additional warming from natural feedbacks. Proc Natl Acad Sci USA 116:759–764.
To get electricity from where it is generated to where it is needed requires transmission lines, which inevitably lose some of the power along the way. Using high voltages and transmitting with direct current (DC) rather than alternating current (AC) help. Doing both is best, and with the ultimate goal of being able to move electricity long distances from isolated renewable sources, ultra high voltage direct current (UHVDC) transmission lines are in planning stages or under construction. The first in the US will be a 700-mile long cable from Oklahoma’s wind farms to Tennessee to connect with the Tennessee Valley Authority grid. Similar initiatives are under way in China, Europe, and Brazil. Some lower voltage DC lines have been operating for years; one transmits power along the east side of the Sierra Nevada mountains from the massive hydroelectric dams on the Columbia River between Washington and Oregon to Los Angeles. Others connect oceanic islands; across the English Channel and between New Zealand’s North and South Islands, for example, where AC is impractical because of the losses from interaction of its alternating magnetic fields with ions in salt water. Continue reading →
Barack Obama has been busy during his last days in office writing well-documented policy articles for major publications. Barely a week before turning over the Presidential reigns to Donald Trump he has commented in some detail in Science about how, in his view, the clean energy horse has left the barn and is unlikely to be stopped even by it’s most fervent detractors (Obama, 2017). He cites four reasons for believing this. The first is that as the US economy has grown, emissions have fallen; since 2008, the amount of energy consumed per dollar of GDP has fallen by 11%, the amount of CO2 emitted per unit of energy has fallen by 8%, and the CO2 emitted per dollar of GDP has fallen by 18%. Furthermore, worldwide the amount of energy-related CO2 emissions in 2016 were essentially the same as 2014, despite economic growth. He also points out that carbon pollution is increasingly expensive. Given the rhetoric of the incoming administration, though, this reasoning alone doesn’t appear to assure continuing in the same direction. Continue reading →
Methane (CH4) is a much stronger—30 times as strong—greenhouse gas than CO2 in the short term, but has a much shorter atmospheric lifetime, being oxidized to CO2 by another atmospheric chemical entity, the hydroxyl radical (OH-). But either the production of CH4 has been increasing, or that of OH- decreasing, because since 2007 atmospheric levels of CH4 have increased by 3% after years of being flat. Why?
Is it the large amounts of CH4 now known to have been released by fracking? This has seemed a likely candidate, but Paul Voosen (2016) writing about a session in the American Geophysical Union annual meeting in San Francisco in December, indicates that the data are not compelling. Continue reading →
The seismicity induced by oil and gas operations in Oklahoma generally appears to be caused by reinjection of wastewater coming out with oil and gas rather than the increase hydraulic pressure from fracking directly. Not so in western Canada where much less wastewater is produced and injected, but there is nevertheless considerable induced seismicity tightly clustered in space and time near hydraulic fracking sites, according to Xuewei Bao and David W. Eaton (2016) writing in Science.
The figure from the paper (above) shows locations of seismicity in northwestern Alberta, anda from 1985-2016. The locations of the largest earthquakes are shown by date. Continue reading →
Should we plan to decrease fossil fuel use as quickly as possible to decrease damage from global warming? Maybe not according to Gustav Engström and Johan Gars (2016), Swedish economists, who consider the possibility that planned reduction of fossil fuel use might cause suppliers of it to increase production now in advance of potential decreased value of it in the future.
Their focus is economically-important climatic tipping points—relatively sudden climatic changes triggered by gradual global warming—that could have drastic economic consequences; they are less concerned with environmental damage with low immediate economic consequences, and they argue that most economists have modelled the effects of climate change without taking climatic tipping points into consideration. These potential tipping points, however, might not exist, in which case, they argue, it would be best to proceed gradually with climate reforms, but develop a strategy to deal with any tipping points should they occur. Continue reading →
Almost half of the coal mined in the US comes from lands, mostly in Wyoming and Montana in the Powder River Basin (PRB), owned by the federal government and which have nearly 10% of the world’s known reserves. Gillingham et al. review the social costs of this coal extraction, and weigh them against the revenues flowing to the government from the leases and the resulting relatively low energy prices paid by consumers. According to their calculations, the monetized climate change damages caused by combustion of this coal are about six times the coal price of $0.51 per million British thermal units, which is only about a third of the price of coal from other major producing basins. Continue reading →
Non-photosynthetic bacteria (most of them) are capable of all sorts of chemical syntheses, especially when bioengineered. But they all require an energy source. What if that source could be light? The obvious thing to do is to implant them with photosynthetic pathways, but this wa-a-ay beyond current bioengineering capabilities, so maybe it would be possible just to hand them energy from miniature solar cells swimming around in the same solution they are living in. This seemingly highly improbable situation has just been accomplished by Kelsey Sakimoto and co-workers at Berkeley to facilitate the production of acetic acid from carbon dioxide by the non-photosynthetic bacteria, Moorella thermoacetica. This uses up the greenhouse gas CO2 while producing a basic chemical that can be “upgraded to high-value products by wild-type and genetically engineered organisms.”
The system works by the bacteria precipitating cadmium sulfide nanoparticles out of the solution in which they reside, When light strikes these nano-particles they carry out photosynthesis, absorbing a photon to produce an electron and hole pair. The electron is then used to synthesize acetic acid from the CO2 in solution. The authors think that this system has the potential to exceed the utility of natural photosynthesis. An additional advantage is that unlike natural photosynthesis which results in biological molecules such as sugars and cellulose which then need further processing to be useful for other purposes, this system just produces acetic acid which is of no utility to the bsctreria, so it remains available for collection in the solution without further processing.
Sakimoto, K.K., Wong, A.B., Yang, P., 2016. Self-photosensitization of nonphotosynthetic bacteria for solar-to-chemical production. Science 351, 74-77.
If by some miracle we as humanity collectively decide to reduce our greenhouse gas emissions enough to keep the planet from heating up by more than 2 ºC, there are going to be lots of fossil fuels left in the ground. Where will they be? For sure, there will be a good deal left: a third of remaining oil reserves, half of natural gas reserves, and over 80% of known coal reserves will still be unused by 2050. These reserves are defined as the sources that could be economically recovered today and that can be assigned a probability of production. For starters, McGlade and Ekins (2015) think that all fossil fuels in the Arctic, and all oil that could obtained by unconventional methods (such as hydraulic fracturing) ought to be left in place. They then look at all known reserves and partition them by cost of production, reasoning that the least expensive will be mined first. And they point out that, given the amount of reserves, the chances of us not using them is stark. Still, they are able to model the probable trajectory of temperatures using a mix of the available fuel sources. As the bottom line, it is abundantly clear that if we were once in fear of running out of fossil fuels, a more pressing current concern is that we might not. Continue reading →
According to the latest runs of a complex computer energy model (CA-TIMES) coming out of the University of California at Davis (Yang et al. 2015), the energy scene across California may be quite different by 2050. The model is not designed to predict what will happen, but instead to examine the economic and policy implications of just about every possible major perturbation of energy generation and use in the state to get us to the current policy goal of an 80% reduction in greenhouse gas emissions from 1990 levels. What results is a series of least-cost scenarios to get to various policy-driven energy endpoints. The bottom line is that greenhouse gas emissions can be reduced enough to meet the 80% goal at low to moderate costs, but not without major investments in wind and solar power generation, production of synthetic fuels directly from biomass using the Fischer–Tropsch synfuel pyrolysis process (more about that in upcoming posts), and hydrogen production and distribution infrastructure to power fuel cells. Continue reading →