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SO I need some general understanding of temperature calculation pertaining to a sun, the distance it is from a planet and the radiant heat loss and interception by a planet and space (empty space) I have looked at various examples but even the wiki on the subject is far too in depth for me to grasp. I will give you an example.



*As the two celestial bodies draw nearer (on one side as this is not elliptical yet ) heat should increase on the basis of 'shadow and darkness intensity.' How would I create an equation to tell the user what the heat is based on the sun's light. Now, I am aware that it would be only the "Global heat average" and I can work with that. If anyone has any suggestions as to how I can calculate or create an equation to simulate regional weather, please help me... I'll need it. I was hoping to link with a live server and just download data periodically and update the information that way... but I like the idea of simulating it if I can. Just lacking in math is a no-no when programming . If you need me to explain more I would be happy to.

-Daryn

And poo... this wasn't supposed to be in newcommers!

Well, assuming that the space is mostly vacuum, you won't have any heat there, only energy. The (kinetic and radial) energy will then be converted to thermic energy upon hitting a planet's surface (very simplified, it would start in the atmosphere and probably loose quite a bit energy before reaching the face of the planet).
Anyhow, I would say it depends very much on the planet's atmosphere how much "heat" you actually get down on the surface.

Just an idea, it doesn't have very much to do with your question though, sorry

True.

Well divising a planetary atmosphere is easy. But the conversion from radial and kinetic to thermic (do you mean thermal) is what I need help with.

Defining the global temp is easier then defining regional temp because it doesn't take into account various land types, reflection % and absorbtion percent singularly but rather wholly. I NEED HELP WITH FINDING THE TEMP PER POINT on a sphere or something like that in order to calculate global average temp..

Also, let's not forget that darkness also brings colder temps. How would I define a change in temp based on that?

Lol a triple post. I feel special and yet some how stupid... I need a small yellow vehicle of some sort. So basically (I am on a mac now without my dbp project mind you) I've created a solar cycle in which kinetic and radial energy are varying throughout the solar year. I have an object simulating the sun, moon and earth. The rotations of each of these objects are scaled down but are accurate to a one billionth of the actual rotational and elliptical orbit of the earth, moon and sun. I have the hours of each day and night, daylight savings and orbital throw of the moon (0.001 = 1 inch of distance from the earth added every year, a year = 365.0001 units of time. With each banking curve the earth slows down... about tow milliseconds per year, per century.

Heat and temp and energy is taken into account with day, night, stormy and solar year. Every 8 or so years the sun begins a new solar cycle which may include several solar storms and so fourth.

About 51 percent of energy is absorbed by the earth's surface which raises temp, 19% absorbed through the atmosphere which raises it's temp, 20 reflected by clouds and for reference- reflection is converted to surface heat transfer- by default the atmosphere and all else is 0 degrees Fahrenheit + energy level divided to give you 5% of the energy as heat + time shine (sun shining or not is added until the temp = 50% or - 50% of the energy reflected & This is standard for all reflections) 6% reflected by atmosphere and 4% reflected by the earths surface. The conversion of kinetic and radial energy is automatically caused when you divide the amount of energy with the percentage of reflection and absorption (before you divide it to give you surface heat transfer. OR= energy=100, temp of item = 0, heat of item after added heat= 50)

NOW if you got through that head ache, what I am trying to do is either find a way to tell that messy equation that the sun is shining on different parts of the earth with a different intensity. Sort of like a radial gradient on a sphere if you had to visualize it. Then, with a little moderating I could simulate climate. From the climate I gain control of the weather, and from the weather I can simulate an entire weather system based on heat, water, and different values I can input to alter various parts of this 'global niche.' SOOOOOO, if any one has some suggestions as to how I can simulate light shining and not shining (and there is a light positioned with the sun) which the whole point to... is the varying temp with shadow. ANY1!!!!!????!!!!! lol

Okay I found a work around for lack of a better term. Rather then actually calculate day and night based on an ever changing sun and earth position... I created a light/dark map that is always angled correctly with the sun and earth... (think of like a gradient light map on a sphere with a light in front of this sphere.) As the sun moves across the Earth's surface, the light/dark/shadow map turns. Now All I need help with is some sort of "POINTER PLUGIN" besides the default DBPro command that can call 0-255 alpha/gray scale data. This way RGB(255,255,255) is full light and "X" heat and RGB(0,0,0) is No sunlight (or 10% sunlight) and "X" heat. IF ANYONE KNOWS OR HAS AN ADDITIONAL POINTER PLUGIN OR CAN "POINT ME" IN THE DIRECTION OF ONE that can call data in such a way, please do so it will be greatly appreciated. And now, I am done posting until some one else does... i mean, come on... four posts... I NEED A LIFE <.> >.<

Assuming the sun to be point source of radiation (which is good for spherical sources of radiation):
]
where Pr is power recieved by the earth
Ps is the power output from the sun = 1,366 watts per meter (decreases with time)
L is luminous efficiency = 93 lumens per watt
r is the distance from the planet to the sun
A is the area( Id suggest an approximation to pi*r^2 for simplicity )

That is for the usual power transfer from the radiating source to an object. I think you should add that before that percent reflection and absorption you just stated. The power is the time rate of energy recieved by the planet. I think you also need to consider the radiation released by the planet to its surrounding since its not a black box, an ideal object that absorbs and does not emit.

I hope it helps.

Ehehehe..Thats very complicated..Compute for the power recieved by the triangle..Use the equation above, the Area is



where v1,v2,v3 are the vectors of the vertex positions of the objects(adjust it to world coordinate systems). The area is the magnitude of the cross product of the v1-v2 and v2-v3. You can access the vertex datas using lock vertex data (if im not wrong) and get vertex data.


r is the vertor difference between the world coordinate position of the sun and the planet
n is the normal vector of the triangular plane which is



Maybe you can just use Newton's cooling to simplify the cooling process of the planet. Just maybe.

In this i get an error due to the lack of mathematical correction... at the end of the parenthesis what symbol is to be used? (+,-,/,*,^,Sqrt)

-Nevermind I got it now

Also, this isn't a "click on point" for the local weather. I am doing this to then simulate the climate of the planet. So actually I need to be able to tell my app what to do based on the temp. I need to apply specific commands to specific conditions that will occur at various locations on this sphere. Using the vector3 commands are great, but for-next loops are out on this one. I need a way to collectively change temp/heat and climate all over the globe at once. Any pointers?

Doesn't suck when you find something to do that few have done... that few know how to do lol.

Thats rather ambitious..HAHAHA..=]

Anyways, As far as I know, climates are due to wind movements and temperature. Winds flow from high pressure area to low pressure area.

Low pressure area has inclement weather.
High pressure area is has light winds and fair skies.

You'll have to identify which points on the sphere has low pressure and which ones have high pressure. Pressure is directly proportional to temperature assuming that density is uniformly distributed on the surface of the sphere. So, everything becomes dependent with temperature.

Its actually more complicated than that. Convection wind currents from the ground to the top can change densities and, that's very complicated mathematically and is mostly probabilistic in nature. So I suggest to just skip that one out. Unless, you have nothing more important to do like save people or something. =]

Hmmm..(Sigh)..The ground of the sphere has larger temperature than the atmosphere above it. The temperature of the air above the ground (a certain triangle on your sphere) is


where t is the change in time
Pr is power recieved by the triangle
N is the number of particles
f is degree of freedom of the gas = 7 for diatomic molecules(air is mostly composed of diatomic molecules)

where R is gas constant 8.314
Na is Avogradros number 6.02E23

Getting a value of N number of particles above the triangle is hard to do. Its related to density, molar mass and volume. That's it for now.


I agree. =]

Okay so basically for the trade winds/ Jet stream(s) I could use a sin/cos function and when the value reaches higher or lower then a certain point walla: High or low pressure. Now converting the values to locations on the sphere... tricky and I have no clue how to really use vector3. I know their purpose and how to manipulate them... but doing this is beyond my knowledge. If anyone has used the vector3 commands to store/place/(W/E)... values on a sphere... PLEASE EXPLAIN YOU METHOD(S) NOT your code.

Back to the sin and cos function... A RND(#) added to the equation could be used as the speed of the winds and if a further equation can be written, the interaction with several currents and such could be equated but this would require severe testing and balancing of such an equation ensuring that the currents produced never, well... stall. Temp could then be affected by radiation, surface temp and wind... wind could then be affected by surface temp and atmosphere temp... surface temp and atmosphere temp by radiation. AH and here's a minor loop... As wind and temp influence each other and are manipulated by temperature and radiation (in a form of rather) we could then begin introducing a simple water cycle.

NOTE:
This type of data system requires passes... in other words: When you simulate something in a mathematical equation via computer, it is much easier to calculate something/anything in one singular HUGE equation... saves time but not cpu speed or virtual memory usage. So for this heat simulation/climate simulation or whatever you want to call it, we need to break up the equation into several parts and keep the data extracted as close to accurate as possible. What does that mean? It means that writing a three mile long equation to simulate weather patterns is out of the question. THUS... accuracy of the data is effected differently and the steps taken to ensure proper data extraction from the internal equation to the external equation (the portion you see on the sphere) IS VITAL. AS SUCH, calculating the heat cycle then water cycle then thermo dynamic cycle then (blah... blah... blah..) separately before combining them is the only way our standard non-super-processing computers can handle all of the data needed to create a self-sustaining weather/heat/water/wind/radiation and so fourth... system.

After that little road bump in this thread I think I am going to take a nap and then write a thesis. Ciao!