The rapid expansion of cities around the world has accelerated in recent decades. If current trends continue, the equivalent of a city the size of London could be created every seven weeks by the year 2050, according to a study at Texas A&M University.
It has become increasingly evident that reducing carbon dioxide emissions is not happening quickly enough to prevent runaway climate change and that negative emission techniques will need to be utilized as well. Negative emissions means removing carbon dioxide that is already in the atmosphere.
A series of reports from both the US Government and from the United Nations has underlined the dangers presented by the increasing effects of climate change. To date, national commitments to reduce emissions have come up short.
It is increasingly clear that the rate at which carbon dioxide emissions are being reduced is not sufficient to prevent dire consequences of climate change. It appears that it will be necessary to try to actually remove carbon dioxide from the air. Such actions are termed “negative emissions.”
The Paris climate accord by nearly 200 countries seeks to reduce global carbon emissions. But how can the actions of these countries be monitored, reported, and verified? It is not an easy task.
Fossil fuel-based power plants are increasingly considering the use of carbon capture technologies as a way to reduce emissions. The biggest challenge to the wide-spread adoption of such technology is its energy cost, which of course equates to economic cost. Present-day power plants equipped with carbon capture systems can use up to 30% of the electricity they generate just to power the capture, release, and storage of carbon dioxide.
Three years ago, Volkswagen was found to have illegally cheated federal emissions tests in the US using devious programming of emission control devices. The subterfuge enabled 11 million passenger cars to meet U.S. emissions standards in the laboratory despite that fact that they actually produced up to 40 times higher emissions than the legal limit in real-world driving.
Earth Overshoot Day marks the date when humankind’s demand for ecological resources and services in a given year exceeds what our planet can regenerate in that year. The deficit for the remainder of the year means we are liquidating stocks of ecological resources and accumulating waste, primarily carbon dioxide in the atmosphere.
Researchers have for the first time calculated the capacity of North American forests to sequester carbon. The detailed analysis by UC Santa Cruz and collaborators in China and Arizona considers two key factors: the natural process of forest growth and regeneration, and effects brought about by climate change.
We use our sense of smell for all sorts of things, like locating food and habitat, avoiding danger, and so on. Fish do as well. But instead of smelling scent molecules in the air like humans do, fish use their nostrils to sense chemicals suspended in water.
The battle to reduce carbon emissions is heavily focused on electricity generation, transportation, buildings, and agriculture, which collectively account for more than 75% of the total. However, there are other sources of carbon emissions that cannot be ignored. Among industrial activities, the production of cement is responsible for 7% of industrial energy use and is the second largest industrial emitter of carbon dioxide. Making cement accounts for about 7% of global emissions.
A recent study published in Nature Climate Change looked at what emission reductions are needed to meet the climate targets of the Paris Accords. The results are sobering.
Methane emissions are a real problem. As a greenhouse gas, methane has at least 25 times the heat-trapping power of carbon dioxide. More than a third of all the methane that humans are responsible for putting into the atmosphere comes from domestic livestock: cattle, sheep, goats and buffalo. In California alone, dairy cows along with a smaller number of beef cattle emit the heat trapping equivalent of the emissions from 2.5 million cars.
Biomass is often touted as a green energy source. Just recently, the US Environmental Protection Agency declared biomass energy to be carbon neutral – a policy already embraced by many European countries. However, burning forests for fuel has hard limitations and ecological consequences.
The revered biologist E. O. Wilson once said that “if all mankind were to disappear, the world would regenerate back to the rich state of equilibrium that existed ten thousand years ago. If insects were to vanish, the environment would collapse into chaos.”
A growing body of work is leading to the conclusion that it may be nearly impossible to prevent global temperatures from rising more than 1.5 degrees Celsius (or 2.7 degrees Fahrenheit) because we are simply not reducing emissions quickly enough. By some estimates, the current level of emissions will lock in that large a gain within the next few years. At that point, the only way to reverse the effects is to remove carbon dioxide from the atmosphere, where it otherwise will stay for hundreds to thousands of years.
With the United States backing away from the Paris climate agreement and with Europe taking a less active role in climate negotiations, China has become the bellwether on global climate change. Recent climate negotiations in Bonn, Germany were rather acrimonious as countries accused other countries of not doing their part or keeping their promises.
Nine years ago, engineer Richard Jenkins broke the world land speed record for a wind-powered vehicle with a sailboat on wheels driving across a dry lakebed at 126 miles per hour. After years of engineering development, his technology has now taken on the form of a saildrone that can autonomously sail the sea gathering ecologic, oceanic and atmospheric data.
Bacteria may have an important role to play in the effort to reduce greenhouse gas emissions. A group of researchers at the University of Alberta are genetically engineering non-hazardous bacteria that consume methane and turn it into fuel.
There is growing interest in the idea of capturing and storing carbon dioxide. Reducing the amount of it we are putting into the atmosphere is essential for limiting the effects of climate change, but even eliminating emissions entirely is not enough because the CO2 already there stays in the atmosphere for decades or more.
