Global Weather

Weather that we actually experience is a small part of a global weather system that really runs our planet.

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There is a tiresome old saw, one I have been guilty of using too often, that goes like this: If you don’t like the weather in Island Park (substitute just about any location you like), just wait a bit, as it will change. There are so many areas where this applies that it is a good definition of weather. It changes. Often. Almost everywhere.

On the ground, weather is strongly influenced by local features such as mountains and lakes. However, there are global factors that set up the entire planet for the weather events that we actually witness.

Because the Earth is tilted and rotates around the sun in an oblong track, the surface of the Earth heats unevenly. A flat stationary planet oriented directly toward the sun would be very different. It is this uneven heating that creates our weather.

Surrounding the Earth is our atmosphere, made up of gas molecules. These molecules exert a pressure upon the Earth. As the Earth heats unevenly, areas of high pressure, where cold dense air is falling (and exerting more pressure), and areas of low pressure, where warm air with excited expanding molecules is rising (leaving lower pressure behind it) are created. Cold air of the high pressure areas moves to fill the low pressure areas. The larger the difference in temperature, the faster the air will move. We call that wind. These winds can blow in any direction, depending on where the high and low pressure areas are.

However, at a grander scale, there are winds that predictably blow in one direction. Convection winds arise when moist warm air from the equator rises up. Eventually, it quits rising and begins to spread toward the north and south poles where it cools and drops and eventually returns to the tropics. There are six of these convection zones globally, and are what are responsible for those occasional chilly north winds. However, most of the wind is deflected to the east because of the spin of the Earth in what is known as the Coriolis Effect, giving us our more usual westerly winds (wind blowing from the west).

Two other predictable winds are the high-altitude jet streams and the trade winds. Jet streams are relatively narrow bands of strong wind (usually over 100 miles per hour) and always move from west to east. They form where cold air and warm air masses meet—when the convection winds rising from the equator meet the cold polar air and again when the returning, now chilled, convection winds meet the tropical air. There are four primary jet streams: one near each pole and two near the equator.  Because of the spin of the Earth, these jet streams are not straight lines and can result in circulating weather systems like hurricanes. Jet streams can quickly move storms across country or, conversely, if a storm is far enough away, can virtually lock it in place until something changes.

Trade winds, on the other hand, consistently blow from east to west and are surface winds. They center around 30 degrees latitude north and south of the equator and form as part of the convection winds. As the warm air of the convection winds rises and cools, some of it consistently drops back toward Earth north and south of the Tropics of Cancer and Capricorn, the lines between which are the tropics.

Finally, there are large bodies of air called air masses. They may be thousands of feet thick and continental in size. The global winds drive these air masses. When a warm air mass encounters a cool air mass, a front forms. If a cold air mass is replacing a warm air mass, it is called a cold front and vice versa.

Despite the joking about changing weather, weather is based on science, not whim, but it is still challenging to predict because of the global scale it all starts with. Learning about this has deepened my respect for weather forecasters. I won’t be so critical when weather reports aren’t perfect from now on.

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Help Idaho Wildlife

When we traveled across the state in October 2017, most of the vehicles we saw using the wildlife management areas did not have wildlife plates. Buying wildlife plates is a great way for non-hunters and hunters alike to support wildlife-based recreation like birding.

C'mon folks, let's help Idaho's wildlife by proudly buying and displaying a wildlife license plate on each of our vehicles! 

See below for information on Idaho plates. Most states have wildlife plates so if you live outside Idaho, check with your state's wildlife department or vehicle licensing division for availability of state wildlife plates where you live. 

And tell them that you heard about it from Nature-track.com!

Wildlife License Plates

Great news! as of 2024, there are three NEW designs for license plates. They still are bluebird, cutthroat trout and elk, but they are beautiful.

Idaho Wildlife license plates provide essential funding that benefits the great diversity of native plants and wildlife that are not hunted, fished or trapped—over 10,000 species or 98% of Idaho’s species diversity. Game species that share the same habitats (such as elk, deer, antelope, sage-grouse, salmon, trout) also benefit from these specialty plates.

No state tax dollars are provided for wildlife diversity, conservation education and recreation programs. Neither are any revenues from the sale of hunting or fishing licenses spent on nongame species. Instead, these species depend on direct donations, federal grants, fundraising initiatives—and the Idaho Wildlife license plates.

Both my vehicles have Bluebird Plates. I prefer the bluebird because the nongame program gets 70 percent of the money from bluebird plates, but only 60 percent of the money from elk and trout plates - 10 percent of the money from elk plates supports wildlife disease monitoring and testing programs (to benefit the livestock industry) and 10 percent from cutthroat plates supports non-motorized boat access.

Incidentally, in 2014, the Idaho Legislature denied the Department of Fish and Game the ability to add new plates or even to change the name of the elk and cutthroat plates (very specific) to wildlife and fish plates, a move that would have allowed for changing images occasionally and generating more revenue. It would seem that they believe that we Idahoans don't want a well funded wildlife program.

I think it is time we let the Legislature know that Idahoan support wildlife funding and that we would like to see these generic plates come to fruition.

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