Weather for the AT

Part 1 the Seasons

Most if on all our external skin detailing is geared to the weather, ok the look, and feel is massive, but the weather is all-encompassing, get it wrong and the building will fail.

So in this series of CPD lectures, I want to outline just what the weather is, the power it can muster and just how we can predict some of the weathers force by good observation looking at the past, and understanding some basic weather law.

This first lecture is all about the Solar System, what you ask, why do we have to look at the stars, well its not the stars, just our immediate part of the solar system, our tilt, orbit and the moon. All three form the basis of all-weather.

The first point of interest is the tilt, Earth in its formation was hit by another planet, astronomers call it Theo, and the earth at this point in time Proto Earth. The collision between the two planets pushed the earths axis into a tilt of 23.4 degrees away from the Earths orbital Plane and left enough debris to allow the moon to form giving the second point of interest in our view of the weather. with an axis of 5.4 degrees away from the earth's orbital plane. The spin we can only assume was also a byproduct of the collision.

Our second point of interest is the orbit itself. Most pictures and solar maps show a circular orbit, but this is so far from the truth, with earth having an elliptical orbit the sun centred not at the middle of the orbit. the nearest point is roughly 90 million mines and the farest point 93.4 million miles

Our  next point of interest is the direction of the tilt, the collision between  Proto earth and Theo pushed the tilt into a particular direction. in that its alined along the longer centre line of the ellipse.

The closest point the earth gets to the sun occurs in early January,when the northern hemisphere is pointing away from the sun and the far point happens in early July when the northern hemisphere points towards the sun

The earth's orbit now gives us the fourth point which is a combination of the orbit, the tilt, the direction of the tilt and the sun not being centred on the suns orbital path to give the fourth point, the seasons themselves. As we discussed earlier, at its apex at both ends of the ellipse, the tilt is either pointing towards the sun, the northern hemispheres summer, and away from the sun the southern hemispheres summer. Add to this the distance for the northern hemispheres hight of summer. 

The difference in distance way from the sun ( 94 million miles away from the sun, called to aphelion or just over 90 million miles, the perihelion, is the reason why the north has a mild summer and the southern hemisphere a rather hot summer. it is also the reason for the daylight change, and the often confusing time  changes each country has.

This difference is what  helps drives the weather, our orbit is fixed for the next million or so years, so is the tilt, although both will slowly change, as will the distance between the earth and the sun, and the sun itself will change too, but the time scales for all these events is very large at millions of years.

The moon is also a major driver for our weather, its orbit and mass drive the tides and pulls the earth's oceans around the planet, which has such a huge impact on the weather, when these tides link with the seasons.

The season are not a wandering phenominan, they are fixed, but how the earth interacts with the seasons is part of a wider picture, of circulating air currents, the mass of the planet, the amount of water with its own currents, both local to land mass, and the larger current that seems to flow around the planet in a never ending loop,  the ice coverage and its complicated relation in regulating the earths weather. plus the moons effect on the earths oceans.

I will look at these areas in more detail in future lectures, but for now all I wanted to do was show the basis of the seasons, the difference between the north and south, and the importance of the moon. To understand the rest of the earth weather machine, as its often referred to, this simple basis of the earths relation to the sun and our moon has to be understood, by any AT wanting to detail correctly,