Monthly Archives: May 2013

Severe Weather and Global Warming

Yet again Moore, Oklahoma has been hit with a monstrous tornado. In 1999 Moore suffered a EF-5 tornado, the most intense in the rating system. The 2013 storm followed essentially the same path, and is quite likely to be another record breaker in terms of intensity and damage.

It’s no coincidence that the National Weather Service Storm Prediction Center is in Norman, OK as this region is known as tornado alley. The area is where collisions of cold fronts from the plains are most likely to collide with warm moist air from the Gulf, the conditions which generate storms and tornadoes. Generally the warmer and more moist the air, the stronger the tornado.May_20,_2013_Moore,_Oklahoma_tornado

So the big question is why this storm now? Is it just a random occurrence or is there a connection with global warming? There is no question that global warming is occurring and is driven by human activities such as burning fossil fuels and worldwide deforestation. 2012 was the hottest year in recorded history in the United States. Last year’s drought in the midwest was the most severe since the 1950’s. Globally, eleven of the hottest years on record since 1880 have occurred in the last twelve years.

The United Nation’s weather agency has confirmed that 2012 was the 27th consecutive year that global land and ocean temperatures were above average. Last year exceeded the global average temperature of 58 degrees Fahrenheit despite the cooling influence of a La Nina weather pattern, according to the World Meteorological Organization’s annual climate report.

As human activities continue to flood the atmosphere with heat trapping gases, the temperature of the atmosphere rises. A warmer atmosphere over time means climate change. Attendant with climate change are variations in weather patterns. Warmer air is wetter air. Precipitation events can become more intense, meaning flooding is more likely. Severe storms which spawn tornadoes are the result of warm moist air colliding with cooler air- the warmer and more moist the air, the more severe the storms. Paradoxically droughts in mid-continental regions are predicted due to changes in weather patterns. Examples abound.

At the expense of repeating myself, no one weather event can be blamed on global warming, but the pattern of events we are seeing are consistent with what one would expect as a result of global warming and climate change.

Are EF-5 tornadoes to be the new normal? Only time will tell, but if these conditions persist in future years not only will the environment be impacted but also the economy. And that is dangerous.

Denial of the risk of global warming persists but is waning. Something like sixty per cent of Americans now believe global warming is happening, and is due to human activities. The denial is somewhat understandable because to accept the reality of global warming is to accept culpability. We individually and collectively don’t want to recognize that when it comes to global warming we are the major actor. Each and every one of us is to blame to some degree.

Ocean Acidification and Global Warming

The planet passed another milestone this week, nothing dramatic just a way point towards the inexorable collapse of ocean fisheries. The milestone is the the fact that the atmosphere now is at 400 parts per million (PPM) Carbon Dioxide, a condition not seen in over 3 million years. Whereas the composition of the atmosphere and climate change slowly over time without human intervention, the unprecedented change now is happening faster than has ever been seen before.

Human activities such as the burning of fossil fuels and deforestation are adding Carbon Dioxide (CO2) to the atmosphere at a geometrically increasing rate. Global_Carbon_Emissions.svg This was happening long before the recent technological advances which have increased the rate that we can produce oil and gas here in the United States. Those advances may look good for energy independence but serve to exacerbate the rate of global warming hence climate change via the release of CO2 to the atmosphere.

If you wondered why I mentioned the ocean earlier here’s why. Of the CO2 added each year to the atmosphere about a quarter is absorbed by the oceans. A lot of gases dissolve in water. If oxygen didn’t dissolve in water, there would be no fish in the seas. But CO2 is unique among atmospheric gases because not only does it dissolve, it also reacts. Carbon Dioxide reacts with water to form carbonic acid.
This is the same stuff of soda pop, it adds tartness to a beverage. It is not a problem for us because we have systems in our bodies which can buffer, basically neutralize, the acidity. No such system exists in the open oceans. If you add more CO2 to the oceans they become more acidic. And this can be a problem of catastrophic proportions.

The shells of many many organisms will not form or actually dissolve in the presence of too much acidity, from the littlest limpets to the corals of the Great Barrier Reef. And herein lies the possibility of a catastrophe. The coral reefs are the nurseries of the ocean.Coral_reef_locations It is here where the food chain begins, and it is here where the ocean fisheries will end if the corals die off. They are already stressed by higher ocean temperatures. Caribbean corals are experiencing a condition known as bleaching, actually dieing. Increased acidity can add to the die-off.

And now there is evidence of acidity impacting ocean organisms. For ocean organisms, the canary in the coal mine is a little known group of animals called sea butterflies. LimacinaHelicinaNOAA Shell thinning among the sea butterflies is occurring making them more susceptible to predation. They occupy the antarctic ocean. Gases are more soluble in cold water so it is not surprising that the effects of acidification of the ocean will be observed in the antarctic ocean first. Just as the canary is more sensitive to toxic gases, the sea butterfly in the antarctic ocean is more sensitive to acidity.

The question becomes just how long do we go on polluting the atmosphere and the oceans? How much damage to the biosphere is enough to convince us to change our ways? H. L. Mencken said it best: It is the nature of the human species to reject what is true but unpleasant, and to embrace what is obviously false but comforting.

Hydropower in Arkansas

Electricity production in Arkansas is similar by source to the rest of the country. For Arkansas, the percentages are coal, 47 percent, nuclear 25 percent, natural gas 15 percent; and hydroelectric, 10 percent. Sustainable sources such as wind and solar electric represent only a fraction of a percent.

An ideal power source would be sustainable, clean and available when needed in the amounts needed. Hydroelectric energy production comes close to this ideal.

Facilities range in size from the generators at Remmel Dam on Lake Catherine with a 9.3 megawatt capacity to the dam at Bull Shoals with 380 megawatts. The dam on Lake Dardanelle comes in second with a capacity of 161 megawatts. Total hydropower in Arkansas is 1,374 megawatts from 15 facilities.

Discussions about energy supplies can get terribly muddled without a clear understanding of three terms: power, energy and capacity factor. Power is the ability to do work, energy is the actual work done and capacity factor is the amount of time actually doing the work.

An example may be helpful. The generators on Lake Dardanelle have a rating of 161 megawatts (power). When the generators run at this rate for one hour, they will produce 161 megawatt-hours (energy). To get the maximum possible annual energy produced, simply multiply by the number of hours in a year.

But they don’t run all the time. Too much water due to heavy upstream rainfall, or too little water, or even varying demands limit the amount of time the dam is generating (capacity factor). The average capacity factor for hydropower in Arkansas is about .47. This means on an annual basis, hydroelectric facilities produce about 47 percent of the energy theoretically possible.

Capacity factors for other energy sources for comparison are about 90 percent for nuclear and 17 percent for solar electric systems. A high capacity factor is not necessarily good, nor a low one bad as the important thing is matching supply with demand. A large reservoir like Bull Shoals is valuable as both long term and short term energy storage. Water accumulates during the winter when there is lower demand for electricity and then is released on hot afternoons in the summer to generate power “on demand.”

The ability to rapidly increase power production is important to meet peak demands. On the other hand, nuclear power reactors are better at providing base load power due to the fact that they run best a full power and are not capable of powering up and down to meet variable loads.

Hydropower is not a perfect solution due to several drawbacks. To be economically practical, they need to be large; therefore, large amounts of land are put underwater. More than 5 million people were displaced by the construction of the Three Gorges Dam in China. The remains of an unusual resort community called Monte Ne lies submerged under Beaver Lake. Occasional mechanical failures of dams have had catastrophic results, and reservoirs have limited lifetimes due to silt accumulation which ultimately limits power production.

Virtually all suitable sites for hydropower in Arkansas have been used. The last battle for a large reservoir, at Gilbert, resulted in the creation of the Buffalo National River. It is over 135 miles and the first federally protected river with the highest bluff and the tallest waterfall between the Rockies and the Appalachians.

Syrian Civil War and Sarin, a WMD

The drums of war seem to be getting louder. In August 2012 President Obama said “ a whole bunch of chemical weapons moving around …that’s a red line for us.” The crossing of the red line would then imply that the US should become involved in the two year old Syrian civil war. So far the evidence seems limited and far from conclusive.

If nothing else we should be wary of weak evidence of the possession or use of weapons of mass destruction as justification for going to war. So lets examine what we do know. What we have to go on is soil samples that were smuggled out of Syria. Laboratory analysis of the samples suggested traces of a nerve gas known as Sarin. Actually because Sarin is quite reactive the only thing to be detected would be hydrolysis products due to the reaction with water in the air or soil. Also there was hearsay evidence of witnesses claiming to have seen victims of exposure to Sarin.

Sarin is a very toxic nerve agent. It actually isn’t a gas but rather a liquid designed to be aerosolized, meaning sprayed as a fine mist. Contact with bare skin or especially inhalation causes a number of symptoms ranging from heavy salivation, profuse sweating, muscle cramps, convulsions and death resulting from respiratory paralysis. Not pretty, huh?

Sarin is a member of a class of poisons known as Acetyl Choline Esterase Inhibitors. Other substances that have the same effect, but lower toxicity are a number of insecticides. Even the relatively safe house and garden type insecticides kill insects by the same mechanism. So how do they work?

Imagine you want to wiggle your big toe. A message travels from your brain via several nerves “talking” to each other to get the signal all the way to your toe. For the signal to get from one nerve to the next requires the opening and then closing of a “gate.”Synapse_Illustration_unlabeled.svg The gate opening allows the signal and the closing stops the signal. If the gate doesn’t close your toe would continue to wiggle. That is the way Sarin and other Acetyl Choline Esterase Inhibitors work. They keep the gate open. A small stimulation of a nerve can’t be turned off. The affected tissue is overstimulated. When the affected tissue is the chest muscles, your breathing is disrupted.

Now back to the weapons of mass destruction. Recall the President Obama said “bunches of” WMDs. The evidence so far for the presence or use is inconclusive. We don’t know who used them if they were used at all. We don’t know how much was used but the only evidence suggests limited rather than widespread use. We don’t know where they were used or how many people were affected. This is not the evidence we need to spend our blood and treasure yet again in the middle east.

Exploding Fertilizer and a Dead Zone

Last week saw a deadly explosion at a fertilizer plant is West, Texas. Several city blocks near the plant were leveled by the explosion, hundreds were injured and over a dozen people killed. The ultimate cause of the explosion has yet to be determined and may never be known exactly but what is known is that several hundred tons of Ammonium Nitrate had been stored there.

Accidental detonation of Ammonium Nitrate stores are rare but when they do occur they are deadly. The most recent before the West, Texas plant involved a fertilizer manufacturing plant in Iowa in 1994. There an explosion killed four and injured a couple of dozen. The granddaddy of all fertilizer explosions occurred in Texas City, Texas in 1947. A freighter in the port of Texas City carrying over two thousand tons of Ammonium Nitrate exploded, leveling the city. The explosion which knocked people off there feet in Galveston ten miles away, killed almost a thousand and injured many thousands more.

These accidents are tragic but accidents just the same. More hideous are intentional explosions such as Timothy McVeigh’s truck bomb in Oklahoma City. He used about 3 tons of fertilizer to destroy the Murrah Federal Building, in the process causing hundreds of millions of dollars of property loss and killing 168 people including 19 preschool children.

So if Ammonium Nitrate is so dangerous, why so much of it? Because as noted it is fertilizer, and a very important one at that. Historically nitrogen from animal dung has been applied to crops. Addition of Nitrogen to the soil improves plant growth, in fact without Nitrogen plants don’t grow at all.

Early in the nineteenth century a concentrated form of Nitrogen fertilizer called Chilean Saltpeter (a form of Nitrate) was obtained from South America. Later a process for manufacturing Ammonium Nitrate synthetically known as the Haber process, was developed in Germany. This process has since been employed world wide and is a key to both large scale agriculture but also large scale explosive manufacturing. Nitrate from the Haber process is used in modern explosives such as dynamite, TNT, and other even more potent munitions.

So Nitrate in explosives is bad, at least the lethality aspect is bad, but Nitrate in fertilizers is good? Up to a point yes, but too much fertilizer used as fertilizer can be bad. When any form of Nitrogen is applied to soil some of it is taken up into plants. If the applied fertilizer is in a soluble form it can wash from the soil into rivers, lakes, and water supplies. Too much Nitrate in drinking water can cause infant deaths due to a condition call Blue Baby Syndrome.

The ultimate insult to the environment from too much Nitrate in waterways is the production of algal blooms. Natural decomposition of the algae consumes oxygen in the water which can kill virtually all aquatic organisms. Every year, a dead zone develops at the mouth of the Mississippi River in the Gulf of Mexico. The dead zone is a hypoxic region, a region with little or no dissolved oxygen. The size of the region varies from year to year, but covers thousands of square miles in the late summer.

As in so many other aspects of life, too much of good thing can cause harm. We need to be good to our mother (Earth). She’s all we’ve got.