does it have an effect on climate change?
Yes, it causes rain.
Cloud
. If the droplets become too large and heavy to be kept aloft by the air circulation, they will fall from the cloud as rain. 
chemical and physical processes include the formation of clouds On Earth, clouds are formed as a result of saturation of the air when it is cooled to its dew point, or when it gains sufficient moisture (usually in the form of water vapor) from an adjacent source to raise the dew point to the ambient temperature. how is it classified? Stratus, cirrus, stratocumulus, cumulus, and cumulonimbus. where is it formed? In the Earth's homosphere where did it get it's name from? The origin of the term "cloud" can be found in the Old English words "clud" or "clod", meaning a hill or a mass of rock, because of the similarity in appearance between a mass of rock , it got the name. what is the reason behind it's luminance? The luminance or brightness of a cloud is determined by how light is reflected, scattered, and transmitted by the cloud's particles. Its brightness may also be affected by the presence of haze or photometeors such as halos and rainbows.
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Cloud [SEP] Luminance, reflectivity, and coloration
During daytime when the sun is relatively high in the sky, tropospheric clouds generally appear bright white on top with varying shades of grey underneath. Thin clouds may look white or appear to have acquired the color of their environment or background. Red, orange, and pink clouds occur almost entirely at sunrise/sunset and are the result of the scattering of sunlight by the atmosphere. When the sun is just below the horizon, low-level clouds are gray, middle clouds appear rose-colored, and high clouds are white or off-white. Clouds at night are black or dark grey in a moonless sky, or whitish when illuminated by the moon.