Monday, January 12, 2015

Weather Monday 1/12/15 (Why we have weather)

Classes at my college stated today and I did not have to go out in this messy weather. Yeah retirement is actually here.


A fabric postcard with lightning made several years ago in an exchange.






My topics for today.

Why do we even have weather on our planet?

That actually happens for a very simple reason. All the Earth’s weather is driven by the Sun. When the Sun shines on the Earth, the tropics get warmer than the poles. This difference in temperature causes the air to move around on our planet. What the air is trying to do is to balance heat and moisture around the world. The warm, moist air from the tropics moves toward the poles and the cold, dry air from the poles moves back toward the equator. So all our weather stems from this simple fact….the equator is warmer than the poles. Storms, hurricanes, typhoons, cyclones, thunderstorms, tornadoes, fronts, heat waves, cold spells, droughts, flooding all come about because of the differential heating of the Earth by the Sun. If we all had the same temperature there would not be all these weather phenomena on our planet.

How does the USA’s weather compare to the rest of the world?

The United States has the craziest weather on the planet. We have terrible winter storms, hurricanes, droughts, thunderstorms and tornadoes. In fact the USA has the most tornadoes of any where on Earth. Yeah we are number 1!  Here is a map of the world showing where tornadoes occur. You can see that the central plains of the United States in the area known as “tornado alley”  has the most tornadoes by far of any other place on Earth.



A lot of people think this area has the most tornadoes because it is flat and that tornadoes do not happen in mountainous areas, but that is simply not true.

Remember that cold, dry air heading back toward the equator and the warm moist air heading out of the tropics toward the poles? Mountains could actually prevent those air masses from meeting and colliding with each other. But in the USA we don’t have any mountains that run east and west to prevent these air masses from running into each other and brewing up supercell thunderstorms and tornadoes. Yes we do have mountains in the United States like the Appalachians and the Rockies, but they mainly run north and south and cannot stop these air masses from colliding. There is a joke that says that the only thing that is there to stop the cold air from slamming into the warm air are only a few snow fences.

Where the cold, dry air and the warm, moist air meet and clash is in the central plains….tornado alley. So all of the tornadoes that happen here are a result of the equator being hot and the poles being cold.

The tropics breed the worst storms on Earth…hurricanes. These terrible killer storms might start in the tropics, but they don’t stay there. The move out of the tropics toward middle latitudes. And where is the USA? You guessed it…middle latitudes. Hurricanes are one of the ways that nature balances heat and moisture around the planet. Certainly not a very nice way and a very expensive way, but that is all these storms are. They are a balancing mechanism. Hurricanes are not very friendly storms, but we give them nice friendly names like Katrina, Bob, Sandy, or Andrew. I guess that is one of the bad things about naming them after people.

I think when they first started naming storms in Australia they named them after politicians they did not like. I could think of a few names. In fact here is a very funny video using that idea. If you are a tea party person, a FOX network watcher, a very conservative republican, or a global warming denier then you will probably will not find it funny and you might not want to watch it. My students were crying last semester because they were laughing so hard when I showed it in class.

Naming storms after politicians!

Well I hope you enjoyed that. One of these Mondays I will address global warming. For now I am going to sign off. Next week I will talk about how accurate forecasts are.

Thanks for reading. If you have questions just ask me.


1 comment:

Bonnie said...

You are still teaching Chris. Loved the video. I have a hard time figuring out how folks don't /can't believe in global warming. Agh. Thanks for the laugh.