how would the angle of the noon sun and the heating of the atmosphere be different at the tropic of Capricorn if the axis of Earth were not tilted as it is
If the axis of the Earth were not tilted as it is, the angle of the noon sun and the heating of the atmosphere at the Tropic of Capricorn would be significantly different. Currently, the tilt of the Earth's axis causes the Tropic of Capricorn to be located at approximately 23.5 degrees south of the equator.
Under normal conditions, during the December solstice, around December 21st, the Sun reaches its highest point in the sky at noon along the Tropic of Capricorn. Since the Earth's axis is tilted, sunlight strikes the Tropic of Capricorn more directly during this time, resulting in more intense heating and higher temperatures in comparison to other latitudes.
However, if the Earth's axis were not tilted, the Tropic of Capricorn would not exist, and instead, there would be a symmetrical equator with no specific latitude experiencing the highest angle of the noon Sun. In this scenario, the heating of the atmosphere would be more evenly distributed throughout the planet, and the concept of distinct tropics and associated climate patterns would likely be altered.
It's important to note that the Earth's axial tilt plays a crucial role in the distribution of solar energy, seasons, and climate patterns. The tilt contributes to the variation in day length, the intensity of sunlight, and the movement of the Sun throughout the year. Removing or altering the Earth's axial tilt would cause significant changes in the angle of the noon sun and subsequently affect the heating of the atmosphere across the entire planet.