terra central

Multi-Year Sea Ice Thins in the Arctic

Professor David Barber of the University of Manitoba Center for Earth Observation Science recently spoke at the International Polar Year conference in Oslo. An excerpt from his talk refers to the sea ice cover satellite data produced by the National Snow and Ice Data Center, which describes areal extent only:

“Scientists spend a lot of energy discussing the ‘squiggly line’ generated by satellite data on sea ice extent,” Dr. Barber told the audience, showing a graph from the National Snow and Ice Data Center. “But extent alone does not reflect the real condition of the sea ice. I think we are all looking forward to getting reliable data on thickness from CryoSat. Because what really matters is the condition and thickness of the multiyear ice.”

“We are losing 70 000 square kilometres of sea ice (the size of Lake Superior) every year. That adds up to 2.5 million square kilometres over the last 30 years. The reality is even worse,” continued Dr Barber. “Even though the extent of the sea ice – both the winter maximum and the summer minimum – increased in 2008 and 2009, the amount of multiyear ice continued to decline rapidly.”

Barber’s observations came from over-wintering in the Arctic aboard a research ice-breaker. Expecting to be stopped by thick multi-year ice up to 12-meters thick, the icebreaker cut through ice only a couple inches thick at 13-knots.

The entire talk is available here.

A Tragic Ignorance of Mineral Weathering

Rainwater harvesting offers a safe alternative to arsenic-tainted groundwater.

Following up on a report from the British journal Lancet, global news agency AFP reports:

“Up to 77 million Bangladeshis have been exposed to toxic levels of arsenic from contaminated drinking water, and even low-level exposure to the poison is not risk-free, The Lancet medical journal reported.

By some estimates, between 35 and 77 million people in Bangladesh have been chronically exposed to arsenic-contaminated water as a result of a catastrophically misguided campaign in the 1970s.”

The “misguided campaign” had the good intention of providing safe water to millions of people living on the vast, low-lying Ganges–Brahmaputra River Delta. The delta receives drainage and sediment from the Himalayan mountains and, due to the wet tropical climate and relative solubility of arsenic-containing soil minerals, the groundwater is contaminated.

Rainwater harvesting is an inexpensive, sustainable alternative to using tainted groundwater for drinking. Expanded use of rainwater harvesting with simple technological enhancements to improve on an ancient practice is showing good results. The problem seems to be difficulty expanding the program fast enough.

Bangladesh, squeezed between the mountains and the sea, and most of which is less than 40-feet above sea level, has the coastal problem of saltwater intrusion into surface freshwater sources. Here is an interesting video on that topic and efforts to build more rainwater harvesting systems.

Further information on Rainwater Harvesting

Sharp Decrease in May Arctic Sea Ice Cover

May saw a sharp decrease in Arctic sea ice cover, based on satellite observations. The average ice cover for the month was about 13 million square kilometers, 500,000 square kilometers less than the 30-year average. The rate of icemelt averaged 46,000 kilometers per day, the fastest rate recorded. The graph above indicates the area of Arctic sea ice is now below two standard deviations of the mean ice coverage observed since 1979. Two standard deviations make up about 95 percent of the data, placing the May data in the skinny “tail” of the bell curve.

Temperatures were 2 to 5 degrees Celsius higher than average over the Arctic while central North America saw colder than average temperatures.

Source: June 8, 2010 Update, National Snow and Ice Data Center

Coast of Alaska: Accelerated Erosion 2002-2007

Alaskan coastal erosion (USGS).

A five-year study in Alaska led by the U.S. Geological Survey (USGS) found that shoreline erosion along a 40-mile stretch of the Beaufort Sea has been accelerating from about 20-feet per year fifty years ago, to 45-feet per year by 2007. The research makes obvious the importance of considering the specific properties of the earthen materials exposed to erosive forces. In this case, the land contains permafrost, a consituent of the soil order called Gelisol.

An excerpt:

The authors proposed that these recent shifts in the rate and pattern of land loss along this coastline segment are potentially a result of changing arctic conditions, including declining sea ice extent, increasing summertime sea-surface temperature, rising sea level, and increases in storm power and corresponding wave action.

“Taken together, these factors may be leading to a new era in ocean-land interactions that seem to be repositioning and reshaping the Arctic coastline,” wrote (Benjamin) Jones and his colleagues. “And any increases in the current rates of coastal retreat will have further ramifications on Arctic landscapes – including losses in freshwater and terrestrial wildlife habitats, and in disappearing cultural sites, as well as adversely impacting coastal villages and towns. In addition, oil test wells are threatened.”

Alaskan permafrost erosion (USGS)

For most of us who live on the relative “terra firma” of the mid-latitude continents, global warming may seem like a fairly benign process, one that might result in better weather to play golf. The Arctic and Antarctic environments, by contrast, are very different, very fragile worlds. The authors are careful with their words, using the standard qualifiers, but it’s pretty clear they think climate change is a factor as the waves pound that coast.

Research Paper:
Jones, B.M., Arp, C.D., Jorgenson, M.T., Hinkel, K.M., Schmutz, J.A., and Flint, P.L. Increase in the rate and uniformity of coastline erosion in arctic Alaska. Geophysical Research Letters, February 14, 2009. http://www.agu.org/journals/gl/gl0903/2008GL036205/.

Photos source: USGS

Methane Venting From East Siberian Arctic Shelf

As a greenhouse gas, methane is 30 times more potent than carbon dioxide.

According to University of Alaska Arctic researchers Natalia Shakhova and Igor Semiletov, methane gas is venting from the East Siberian Arctic Shelf (ESAS) at a surprisingly high rate. The vents are coming through leaks in permafrost, which forms a cap over methane stored in deeper sediments.

While permafrost is generally viewed as a terrestrial soil, it actually extends offshore beneath a broad area of shallow marine sediments. This area of marine permafrost, about 2 million square kilometers, is the most unstable in the Arctic after several years of warming temperatures.

In the video Shakhova indicates the rate of methane venting at the ESAS equals the methane emitted currently by the rest of the global ocean.

Wisconsin Bill Favors Local Renewable Energy

Wisconsin bill would promote small-scale distributed renewable power generation.

While the deeply-divided Congress looks incapable of passing any serious legislation, states are moving ahead with renewable energy initiatives, particularly states that don’t mine coal or drill much oil and gas.

Wisconsin’s Clean Energy Jobs Act (AB 649/SB 450) was introduced January 7, 2010. It proposes major energy reforms recommended by Governor Doyle’s Global Warming Task Force. The bill isn’t just about climate change mitigation, though, it’s about investing in the state. If enacted the bill would:

1. Raise the renewable energy standard to 25% by 2025.
2. Establish renewable energy buy-back rates.
3. Include renewable biogas from Dairy operations
4. Requires 10% of energy production from in-state renewables by 2025.
5. Recommendation for zero-net energy usage in new construction by 2030.

According to a summary prepared by RENEW Wisconsin:

“The legislation would require the PSC to order electric utilities to purchase renewable energy, under certain terms and conditions, from renewable energy facilities that are constructed after the effective date of the PSC’s order. Such ART orders must include the following:

* A maximum limit on the generating capacity for qualifying facilities.
In ordering ARTs, the Commission is charged with meeting the purpose of “maximizing the development of small-scale, distributed, renewable generation technologies without unreasonable impacts on electric utility rates.”

The bill, if passed would be one of the most aggressive renewable energy packages found in the United States and mean building hundreds or even thousands of wind turbines by 2025.

Ample Evidence of Global Warming

“the sea still rises.”

American coastal geologists Orin Pilkey and Rob Young have published this article on global warming in today’s Philadelphia Inquirer. Their position: “plain evidence of global warming abounds.”

The article, in the literary sense, takes the reader on a flight beginning with the North Carolina Outer Banks to observe dead trees along a drowning Albemarle Sound and an eroding stretch of barrier islands.

The flight then heads northwest, across the Canadian Rockies to look at shrinking alpine glaciers. Then, on to Alaska and a coastal community built on permafrost. Melting permafrost coupled with coastal erosion, worse now since the sea remains ice-free more months of the year, threatens to take out the village. From Pilkey and Young:

“Clearly, the Earth has revealed undeniable evidence of rising sea levels – drowning shorelines, shrinking arctic sea ice, warming oceans, and melting permafrost and ice sheets. It’s all there for anyone to see.”

Would Americans shut down all the medical schools, hospitals, and clinics if they found out a few doctors were guilty of malpractice? As ridiculous as that may sound, the global warming deniers frothing over bad behavior on the part of some IPCC and University of East Anglia climate researchers seem to be suggesting a comparable purge of global warming research.

Carbon Sequestration by Mineral Carbonation

Given the evidence supporting the view that burning fossil fuels is contributing to global warming and a a potential dangerous climate perturbation, there’s considerable interest in carbon storage. So-called Carbon Capture and Sequestration (CCS) could be done many ways such as increasing soil organic matter and planting more trees, ocean storage, burial in deep geologic formations, and mineral carbonation.

Howard Herzog of the MIT Laboratory for Energy and the Environment has this assessment of prospects for CCS by way of carbonation, i.e., formation of carbonate minerals.

Thermodynamically, the plan makes sense as the formation of both calcite and magnasite releases heat (exothermic) as shown here:

CaO + CO2 =  CaCO3 + 179 kJ/mole
MgO + CO2 = MgCO3 + 118 kJ/mole.

The article claims “calcium and magnesium are rarely available as binary oxides.” Instead, carbon dioxide could be reacted with dissolved magnesium silicates, forsterite and serpentinite, in an anion exchange reaction to form magnesite (MgCO3), like this:

½Mg2SiO4 (Forsterite) + CO2 = MgCO3 (Magnesite) + ½SiO2 + 95kJ/mole

1/3Mg3Si2O5(OH)4 (Serpentine) + CO2 = MgCO3 (Magnesite) + 2/3SiO2 + 2/3H2O + 64kJ/mole

Again, since the reactions are exothermic, the reactions should proceed to the right, the lower energy states. A big andvantage of this process, if feasible, is permanent carbon storage. Other proposed CCS techniqes may leak back to the atmosphere.

There are problems with mineral carbonation, though, involving solubility of the reactants and kinetics. It turns out the forsterite and serpentine need to be dissolved in acid or molten salts, which are both potentially messy and expensive operations. Or, the rock can be ground into a fine powder and dissolved in a hot water solution. The rock grinding consumes a lot of energy.

Such a scenario would require setting up the mineral carbonation factory at a large serpentinite mine where such rocks exist – Quebec, for example. The process would basically dig up one kind of rock, make a carbonated rock, and stuff the new rock back in the hole. The biggest obstacle to making it work, according to Herzog, seems to be finding an economical way to speed up the chemical kinetics.

CCS is a brand new technology and there are no doubt many ready to set up shop and get there hands on some of the big federal economic stimulus money. We’ll need to watch out for snake oil salesman. Herzog does not enthusiastically endorse the process described above but, rather, recommends a “portfolio approach” consisting of a diversified package of strategies.

Like all good researchers, he recommends more study.

Herzog’s article quotes significantly from the following:

Yegulalp T.M., K.S. Lackner and H.J. Ziock, “A Review of Emerging Technologies for Sustainable Use of Coal for Power Generation,” presented at Sixth International Symposium on Environmental Issues and Waste Management in Energy and Mineral Production, Calgary, Alberta, Canada, May 30-June 2 2000).

Soil: The foundation of the economy

Craig Mackintosh, who writes at Celsias has a good article called Soil: Our Financial Institution that identifies the soil as the foundation of our physical and even financial well-being.

Without stealing his “thunder,” Craig does a good job of introducing biogeochemical processes in the soil and the potential soil has for sequestering carbon. Incredibly, there is more carbon, globally, stored in soil than in the atmosphere and living vegetation combined.

Craig’s article contains a map of degraded soils worldwide. I don’t want to minimize the role of burning fossil fuels in raising atmospheric carbon dioxide over the last 100-years, but the degradation depicted in the map involves, in part, loss of soil organic matter, which has been lost from either accelerated erosion or decomposition due to regular plowing. Plowing aerates the soil, speeding the process of organic matter decomposition, and exposes the soil to erosive forces.

Oceanographers and climatologists are concerned with ocean acidification. Much of the ocean acidification is due to soil carbon entering the ocean either as sediment or dissolved carbon carried by rivers.

So, you start talking about soil and soon you’re talking about the ocean and atmosphere.

What to do? The key is to use best management practices that minimize erosion. Growing perennial crops is preferable to annuals as perennials do not require working the soil and planting every year. This is one of the reasons that ethanol derived from sugar cane is more efficient than making ethanol from corn. This is why cellulosic ethanol from switchgrass or wood chips is more efficient than ethanol made from corn.

Converting to perennial root-dense grasses (like switchgrass) instead of annual row crops such as corn would also store more carbon in the ground than would be harvested as crops. This would restore some of the carbon to the soil that has been lost over the past 100 years, or so, due to tillage, oxidation, and erosion.