Tag Archives: climate change

Future US megadroughts set to be the worst in 1,000 years

I believe Thomas Homer-Dixon was talking about this a decade ago.

“These future droughts are not only going to be bad compared to what we’ve experienced over the historical period, but also really bad compared to the past millennium,” says Benjamin Cook, a drought researcher at NASA’s Goddard Institute for Space Studies in New York City, who led the work. “It’s going to be a pretty much fundamental shift.”

Much of North America has a long and detailed climate history, thanks to tree rings that preserve records of temperature and rainfall. Many scientists have used these to piece together the story of decades-long droughts, like one that gripped the US Southwest in the thirteenth century and probably contributed to the disappearance of ancient Pueblo peoples. Others have used global climate models to study the region’s future, and found that it may already be transitioning to a fundamentally drier state.

Cook’s team aimed to bridge past and present. The scientists compared 1,000 years of North American climate history with future projections from 17 different climate models — “as many as we could get our hands on that gave us the data we needed”, Cook says.

Among other metrics, the researchers looked at a measure known as the Palmer Drought Severity Index, which is an indicator of soil moisture. Some scientists criticize the Palmer index because it can overestimate future drying if it is calculated on the basis of temperature projections alone. To get around this problem, Cook’s team used a different method of calculating the index, one that incorporates humidity and energy from sunlight.

Kevin Anchukaitis, a palaeoclimatologist at the Woods Hole Oceanographic Institution in Massachusetts, says that the revised method gives a much more accurate projection of how dry things will really get. “This is the first convincing demonstration I’ve seen that it is both possible to seamlessly connect past, present and future, and to then be confident that they are on comparable scales,” he says.

Human activity has pushed Earth beyond four of nine ‘planetary boundaries’

Uh oh

At the rate things are going, the Earth in the coming decades could cease to be a “safe operating space” for human beings. That is the conclusion of a new paper published Thursday in the journal Science by 18 researchers trying to gauge the breaking points in the natural world.

The paper contends that we have already crossed four “planetary boundaries.” They are the extinction rate; deforestation; the level of carbon dioxide in the atmosphere; and the flow of nitrogen and phosphorous (used on land as fertilizer) into the ocean.

“What the science has shown is that human activities — economic growth, technology, consumption — are destabilizing the global environment,” said Will Steffen, who holds appointments at the Australian National University and the Stockholm Resilience Center and is the lead author of the paper.

These are not future problems, but rather urgent matters, according to Steffen, who said that the economic boom since 1950 and the globalized economy have accelerated the transgression of the boundaries. No one knows exactly when push will come to shove, but he said the possible destabilization of the “Earth System” as a whole could occur in a time frame of “decades out to a century.”

The researchers focused on nine separate planetary boundaries first identified by scientists in a 2009 paper. These boundaries set theoretical limits on changes to the environment, and include ozone depletion, freshwater use, ocean acidification, atmospheric aerosol pollution and the introduction of exotic chemicals and modified organisms.

Beyond each planetary boundary is a “zone of uncertainty.” This zone is meant to acknowledge the inherent uncertainties in the calculations, and to offer decision-makers a bit of a buffer, so that they can potentially take action before it’s too late to make a difference. Beyond that zone of uncertainty is the unknown — planetary conditions unfamiliar to us.

“The boundary is not like the edge of the cliff,” said Ray Pierrehumbert, an expert on Earth systems at the University of Chicago. “They’re a little bit more like danger warnings, like high-temperature gauges on your car.”

Why scientists are (almost) certain that climate change is man-made

From the Economist

ON NOVEMBER 2ND the Intergovernmental Panel on Climate Change (IPCC), which represents mainstream scientific opinion, said that it was extremely likely that climate change is the product of human activity. Extremely likely in IPCC speak means having a probability of over 95%. The claim forms part of its fifth assessment on the state of the global climate. In its first assessment, in 1990, the IPCC had said that “the observed increase [in air temperatures] could be largely due to natural variability.” Why have climate scientists become so much more certain that climate change is man-made, not natural?

Many factors influence the climate but perhaps the single most important is carbon dioxide (CO₂). CO₂ absorbs infra-red heat at a constant rate and at a higher rate than nitrogen and oxygen—the main constituent parts of the atmosphere—so the more CO₂ in the air, the more the atmosphere will tend to warm up. Scientists attribute climate change to human activity mainly because people have been responsible for large increases in CO₂. At the start of the industrial revolution, in about 1800, there were 280 parts per million (ppm) of CO₂ in the atmosphere. That had been the level for most of human history. This year, however, concentrations exceeded 400 ppm, the first time it had reached that level for a million years.

Most of the increase has been caused by people burning fossil fuels. In the United States, for example, 38% of the COâ‚‚ produced in 2012 came from generating electricity and 32% came from vehicle emissions (the rest came from industrial processes, buildings and other smaller COâ‚‚ production). People also produce COâ‚‚ when they cut down forests for farmland and pasture

Effects of climate change ‘irreversible,’ U.N. panel warns in report

More bad news on climate change from the United Nations

The Earth is locked on an “irreversible” course of climatic disruption from the buildup of greenhouse gases in the atmosphere, and the impacts will only worsen unless nations agree to dramatic cuts in pollution, an international panel of climate scientists warned Sunday.

The planet faces a future of extreme weather, rising sea levels and melting polar ice from soaring levels of carbon dioxide and other gases, the U.N. panel said. Only an unprecedented global effort to slash emissions within a relatively short time period will prevent temperatures from crossing a threshold that scientists say could trigger far more dangerous disruptions, the panel warned.

“Continued emission of greenhouse gases will cause further warming and long-lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts,” concluded the report by the United Nations’ Intergovernmental Panel on Climate Change (IPCC), which draws on contributions from thousands of scientists from around the world.

The report said some impacts of climate change will “continue for centuries,” even if all emissions from fossil-fuel burning were to stop. The question facing governments is whether they can act to slow warming to a pace at which humans and natural ecosystems can adapt, or risk “abrupt and irreversible changes” as the atmosphere and oceans absorb ever-greater amounts of thermal energy within a blanket of heat-trapping gases, according to scientists who contributed to the report.

Meanwhile in Canada, we don’t care about climate change, only our own economy.

Canada’s hopes of securing an outlet for its landlocked oil wealth and pulling an end run around the eternally deadlocked Keystone XL project took a big step forward Thursday with the release of formal plans to build a U.S. $11 billion pipeline to the Atlantic.

TransCanada, the biggest Canadian pipeline company, submitted its application to Canadian energy regulators for a nearly 3,000-mile-long, million-barrel-a-day pipe running from oil-rich western Canada to refineries and shipping terminals in the east. The so-called Energy East Pipeline Project, which TransCanada officials hope could be in operation as soon as 2018, would provide an export outlet for huge volumes of current and future oil production that right now has no easy way to get to market.
The project wouldn’t replace the Keystone XL pipeline — Canada’s other high-profile, multibillion-dollar oil-transport project, which has been awaiting U.S. approval for years — but it could give Republican critics of U.S. President Barack Obama’s administration fresh fodder ahead of the midterm elections. Republicans have long argued that the White House’s refusal to sign off on the Keystone project would cost the United States tens of thousands of jobs. The Obama administration has finished reviewing the environmental merits of Keystone, but pushed back any decision until later this year or early 2015.

If the new Canadian route gets approved in 2016 by Canada’s National Energy Board, as TransCanada expects, it would give the eastern provinces a source of domestic oil — removing the need for some 700,000 barrels a day of oil imports — and would give producers in Alberta and Saskatchewan a direct route to big refineries that could turn the sludgy tar sands into valuable products such as diesel, gasoline, and jet fuel.

Over in Germany

On any given day, Johannes van Bergen, director of the municipal utility Stadtwerke Schwäbisch Hall in southwestern Germany, conducts his team’s array of gas, heat, and electricity sources to meet the energy needs of at least several hundred thousand Swabians in the region, as well as about more than 90,000 customers elsewhere in Germany. And every day — in fact, every hour — that energy mix is constantly in flux.

Technicians at the town’s smart-grid center monitor and manage the utility’s roughly 3,000 regional energy suppliers: several thousand solar photovoltaic (PV) installations, two wind parks, one gas-and-steam power station, six small hydro-electric works, three biomass (wood pellet), sixbiogas plants, and 48 combined heat and power plants, as well as other conventional and renewable energy suppliers outside the municipality.

The population that this ballet of coordinated energy sources serves is admittedly modest, but it’s here that the future of Germany’s energy industry is being tested in full — and proven.

Which of course is a model that we could use here but for whatever reason, the province and the country isn’t willing to experiment.

Their output, and increasingly that of the conventional, too, is distributed through a tightly knit, cross-border smart grid. The composition of supply changes from minute to minute depending on weather, demand, and other factors from one corner of the country to the other. Increasingly electricity is generated in and traded from locality to locality, and even across the country (or countries) via intelligent networks much like that in Schwäbisch Hall and other places in Germany.

No one predicted this scale of locally driven, citizen-led energy boom when the Energiewende began. Even just four years ago, just about everybody involved in the Energiewende thought that big-ticket projects like enormous offshore wind farms planned for Germany’s northern seas and Desertec, the mega-project to import solar energy across the Mediterranean from sprawling concentrated solar power arrays in the Middle East and Northern Africa, would be integral to Germany going renewable.

These projects, however, have flopped spectacularly.

Offshore wind has proven extremely pricey and technologically much trickier than originally assumed, which has led to billons in cost overruns and years-long delays. Germany’s seven operational offshore parks constitute a tiny fraction — just 0.6 percent — of the country’s renewably generated electricity, compared to onshore wind’s 34 percent. The offshore industry claims there’s smooth sailing for offshore wind just around the corner, but it’s been saying that for years.

What happens to a countries maritime assets when it disappears beneath them?

From the Boston Globe

The president of the Pacific atoll nation of Kiribati, which averages only about 2 meters above sea level, has already spent millions of dollars to buy land in Fiji as a potential new home for his 100,000 people. As sea levels rise, the Intergovernmental Panel on Climate Change suggests, large ocean waves will increasingly taint the country’s groundwater and threaten its agriculture; Kiribati can expect to become at least partly uninhabitable long before seas rise enough to submerge it. Other island nations like the Maldives and Tuvalu face the same plight.

So far, the world’s attention has rightly focused on how much these places have to lose: their homes, their communities, their cultures, their vistas. But these countries have another, less visible set of assets at stake as they consider their survival—assets that won’t necessarily be lost, but which raise substantial questions. These are their large and valuable maritime zones.

Kiribati, like other island nations, controls hundreds of thousands of square miles of the ocean that surrounds it. Kiribati’s land area is about that of Kansas City, while the ocean territory it controls is larger than India. Within these “exclusive economic zones,” to use the UN term, island nations possess the power to regulate, tax, or disallow any economic activity, including mining or drilling for oil. The tuna fishing alone in the domain of Pacific island nations is worth an estimated $4 billion a year.