Of course, not all types of clouds react this way, or we would never hear complaints about cloudy weather hindering viewing of the eclipse. A team of scientists from the Royal Netherlands Meteorological Institute and Delft University of Technology determined that cumulus clouds, especially over land, disappear very quickly. According to the leader of the research, Victor Trice, this result is has implications for future climate engineering efforts.

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One of the proposed solutions to mitigate climate change is to block a small percentage of the sun’s rays. Thus, it will not reach the lower layers of the Earth’s atmosphere and will not heat the atmosphere. While simulations show this could effectively reduce temperatures, we don’t know what other effects this might have and how long they might last. But If we block the Sun with technological solutions in the future, it may affect clouds. Less clouds will reduce the effectiveness of solar geoengineering because clouds reflect sunlight and therefore actually help cool the Earth. So, on the one hand, we will reduce the amount of sunlight, and on the other hand, we will increase it by eliminating clouds.

It is not easy to understand the behavior of clouds during an eclipse from the Earth’s surface. Cloud layers can be quite complex and their configurations are constantly changing, so counting clouds on Earth is not a convenient method of determining how a solar eclipse affects them. Another option is to study them from above using satellites. But there’s a problem here: This method does not take into account the Moon’s shadow during the eclipse in its cloud surface reflectance calculations, which leads to errors in cloud cover and cloud thickness measurements.

Treece and his colleagues found a way to account for the moon shadow by accounting for the portion of the Sun that is blocked from each point on the Earth’s surface at a given time. “Most solar eclipses occur as partial eclipses, when there is still plenty of light outside. During a partial eclipse, satellites receive enough reflected sunlight to reliably measure clouds after the eclipse has been corrected.”says the scientist.

The researchers applied their method to data collected during three solar eclipses that occurred on the African continent between 2005 and 2016. They found this Cumulus clouds begin to disappear in large numbers when only 15 percent of the Sun is coveredand do not return until the end of the eclipse.

Results of cloud evolution model during solar eclipse / Photo: Viktor Tris

Since it wasn’t clear exactly why this was happening, the team ran simulations using cloud modeling software called DALES. These simulations showed that when sunlight is blocked, the surface cools and the warm air rising above the surface decreases.

Warm updrafts play an important role in the formation of cumulus clouds. They carry water vapor, which condenses into droplets, rising to colder altitudes and forming clouds.

So, when the surface of the planet cools and these upward movements stop, the cumulus clouds cannot last and only persist when the Sun reappears and begins to warm the land again. This effect only occurs on land because the ocean does not cool fast enough for the effect to occur.

Cumulonimbus clouds themselves are not rain clouds, but they can turn into rain clouds. The team’s conclusion shows that Climate geoengineering, which involves blocking sunlight, can have a highly detrimental effect on weather conditions.because the disappearance of the clouds will lead to other consequences and the following. We need more research as this defeats the purpose.