The ethnobotany of Mesquite trees is extensive. The trees provide food, medicine, beverages, glue, hair dye, firewood, and furniture. Mesquites coevolved with large herbivores such as mammoths, mastodons, and ground sloths, which ate the pods and dispersed them widely. When these Pleistocene animals became extinct, mesquites retreated to flood plains and washes where water and weathering scarified the seeds and aided germination. The introduction of cattle helped to expand the range of mesquites once again.

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The summer monsoon is upon us and hopefully it will bring much needed rain. But it will also bring lightning and destructive winds. The term “monsoon” does not mean rain or storms, but a seasonal shift in wind patterns. During the winter, Arizona air flow is usually from the west and we receive the remnants of Pacific storms. During the monsoon, the air flows from a southerly direction bringing us moist air from the Gulf of Mexico, the Gulf of California, and the tropical Pacific. The desert heat and orographic uplift from mountain ranges turn that moist air into thunderstorms.

The graphic below from the National Weather Service shows the parts of a monsoon thunderstorm. The storm is moving left to right.

The first stage of thunderstorm development is the updraft where warm, moist air is lifted by columns of hot air rising in desert valleys or by air passing over a mountain range. This uplift causes water to condense to form cumulus clouds. Falling water droplets pull the air down with them to form the downdraft and rainy part of the storm. The strong downdraft causes a dust cloud, the Haboob, in front of the storm. Frequently dust devils dance in front of the Haboob. As the storm progresses, the downdraft can produce destructive microbursts of high wind. “Gustnadoes” are tornado-like vortex, similar to dust devils, but stronger, that appear to develop on the ground and extend several hundred feet upward. These vortices generally develop along the leading edge of an outflow boundary from a thunderstorm cell. Although generally of limited duration, the winds of gustnadoes can be strong enough to cause damage.

Some safety tips about lightning:

Lightning often strikes outside of heavy rain and may occur as far as 10 miles away from any rainfall. As a rule of thumb, if the time between lightning flash and thunder is 30 seconds or less, the lightning is about 6 miles away. Research has shown that the most successive flashes are within 6 miles of the first one, which means that you should have reached a safe place if lightning is less than 6 miles away.

If possible stay indoors or in an automobile. If outside, avoid isolated tall structures such as trees and power poles. Get off and away from open water. Avoid open metal vehicles such as tractors, farm equipment, motorcycles, and golf. Avoid power lines, wire fences, metal pipes and railings. If you are caught in an open area far from shelter, and you feel your hair stand on end, lightning may be about to strike you. Drop to your knees and bend forward putting your hands on your knees. DO NOT lie flat on the ground, that makes you a bigger target and a better conductor of electricity. Stay away from running water inside the house; avoid washing your hands or taking a bath or shower. Electricity from lightning has been known to come inside through plumbing. When inside, stay away from TV sets, electrical appliances, bathtubs and sinks, do not talk on the telephone, or play on the computer, don’t touch an electrical cord or outlet.

Be aware and be safe.

BP’s Deepwater Horizon Gulf oil spill has caused environmental and economic damage and a political circus. Have you ever heard of the National Oil and Hazardous Substances Contingency Plan Act? This law was passed in 1994 and it specifically charges the Environmental Protection Agency (EPA) with mitigating damage from major oil spills. In response to that act, the EPA, itself, says, “When a major oil spill occurs in the United States, coordinated teams of local, state, and national personnel are called upon to help contain the spill, clean it up, and ensure that damage to human health and the environment is minimized. Without careful planning and clear organization, efforts to deal with large oil spills could be slow, ineffective, and potentially harmful to response personnel and the environment. In the United States, the system for organizing responses to major oil spills is called the National Response System.” The Act makes a prompt and effective response to a major oil spill a national priority. So how are they doing?

Some (mainly conservative) columnists have attributed Obama’s Nero-like lack of concern to ulterior motives. For instance, Obama’s refusal to accept aid from the Dutch government is said to be a sop to the labor unions. And, Obama is using the oil spill disaster to renew his push for Cap & Trade climate legislation.

Maybe there are ulterior motives, but more likely, the less-than-prompt and effective response is probably due to incompetence by Obama and his bureaucracies, just like FEMA’s failure after Katrina. For instance the EPA dithered while considering the possible toxic effects of an oil dispersant that BP wanted to use. Louisiana Governor Bobby Jindal is incensed with the Coast Guard because they stopped cleanup efforts to check whether the crews had proper fire extinguishers and life vests.

Meanwhile, Congress is holding hearings, with all their sound and fury, in a feigned effort to investigate BP (and give “face time” to legislators). Such hearings have no practical value in mitigating the oil spill.

Obama used the oil spill as an excuse to impose a six-month moratorium of deep water drilling, possibly to promote more “alternative energy” schemes. Obama said is was for “safety” concerns by the Department of the Interior, but analysis by the Wall Street Journal shows that this was all about politics. Another possible ulterior motive: the oil spill and Obama’s moratorium will aid Obama contributor George Soros who is heavily involved in Brazilian oil. Brazil stands to benefit from the BP oil spill catastrophe as the US moratorium makes more rigs available for other countries.

Yes, BP should be held responsible for the loss of economic activity caused by the accident. But government action, and inaction, is making things worse. They are not letting a good crisis go to waste.