Why are the areas in the equator not as hot and dry as deserts even though they’re closer to the sun?
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The sun is 93,000,000 miles from Earth (more or less) and the Earth is 7,900 miles in diameter. There’s no real difference in distance from the Sun to any given spot on the Earth. In other words, distance to the sun has nothing to do with why equatorial regions tend to be hot and arctic regions tend to be cool (and temperate regions somewhere in between). It’s the apparent angle of the sun’s incoming rays and global and local weather patterns that cause temperature differences among the various regions of the Earth. Local geography and ocean currents can exert a greater influence than latitude.
“Closer to the sun” is irrelevant; the sun is 93M miles away from everywhere on Earth.
What does matter is that the tropics are face-on to the Sun, so they get more heat. Which causes an upwelling of air, which then cools, forming clouds. The air then descends north and south of the equator. As it does, its temperature increases and humidity decreases, producing belts of arid regions around the globe.
https://en.wikipedia.org/wiki/Hadley_cell
The closeness to sun is not the only factor making a place hot.
Other factors maybe-
Closeness to water body.
Monsoon patterns.
Vegetation in the area.
Deserts are generally open vast lands with no mountains or hills to hold the monsoons and therefore see very less rain making the region extremely dry and eventually sandy. It is devoid of vegetation due to less rains which further takes it temperature to the extremes.
Because being closer to the sun doesn’t have anything to do with how hot it is. Changing elevation, or even the parts of our orbit that are closer to the sun are such a small portion of the distance between us that it had almost no effect.
Temperature/seasons are caused by the angle of our planet and how much direct sunlight we receive. Now, as far as humidity and temperature, a lot of that is affected by moist air being moved around by currents around the equator, but I don’t understand enough of that specifically to comment on it.
By extension, if I’m not mistaken, since our axis of rotation is tilted, the equator isn’t even the closest place to the sun. Not all the time at least.
So first of all, deserts are not all that hot on avarage. Sure they get crazy hot at noon during summer, but they also get quite cold at night and during winter. The avarage temperature of the Sahara is 17.5°C compared to 25°C in the amazon.
The areas around the equator do in fact get the most energy from the sun. Although this has nothing to do with the distance to the sun – a few thousand extra miles are irrelevant here – but with the angle that this sunlight hits the Earth.
And because these areas get the most energy, the air heats up there the most, and hot air usually rises. But since air also gets colder as it rises, and cold air can hold less water vapour than hot air, the vapour condenses into rain. Thats why these areas have so many rainforests.
The air, which is now much drier air, has to come back down somewhere else – usually 20-30 degrees north and south of the equator. So, these areas usually only get air with little to no water in it, which means they don’t experience rain, which makes them deserts. Thats why most of the equator is covered in rainforests, while the deserts are at these other latitudes.
Little bonus fact: The areas that get the most energy shift during the year – in June, they’re somewhat north of the equtor, and in December, they’re south of it. This is what causes, among other things, the “rain seasons” in certain parts of the world.
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