Address Latif/Reuters
Enthusiasts watch a total solar eclipse near Mitchell, Oregon, on August 21, 2017.
CNN
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Saturday’s ring of flame annular solar eclipse When deployed in the sky, they change weather conditions on the Earth’s surface.
When the moon passes in front of the sun and casts a shadow on the Earth’s surface during a solar eclipse, changes in temperature, wind speed, and humidity occur.
The more sunlight is blocked, the more dramatically the weather changes. This effect is comparable to a shady area being much cooler on a hot day than an area in direct sunlight.
Saturday’s annular solar eclipse will block up to 90% of the sun from a narrow path from Oregon to Texas.annular solar eclipse Slightly more solar radiation (sunlight and energy) is able to reach the Earth’s surface than in a total solar eclipse, where the sun is completely blocked.
But any reduction in solar radiation, no matter how short-term, can affect temperatures and other weather conditions.
However, not all eclipse weather changes occur equally. The exact drop in temperature will vary widely depending on the time of year and other factors such as cloud cover.
The annular solar eclipse in October will have a less dramatic effect on temperatures than the total solar eclipse in August, not only because of the amount of sunlight blocked by the moon, but also because the sun hits the Earth at a lower angle in the fall than in the summer. It is thought that there are few. .
As the sun’s angle increases, the sunlight becomes stronger and the temperature rises, and in autumn the angle begins to decrease.
2017 total solar eclipse Because it occurred on a summer afternoon in August, temperatures were already high, making some locations along the path of the totality more prone to cratering. Temperatures in Douglas, Wyoming, dropped 11 degrees in just an hour, and across the South, widespread temperatures dropped by 4 to 8 degrees.
Jonathan Ernst/Reuters
People watch a total solar eclipse approach from Tennessee’s Great Smoky Mountains National Park on August 21, 2017.
The drop in temperature during Saturday’s eclipse is not expected to be as steep, but it could still drop several degrees. circular path.
Juan Hernandez, a meteorologist with the National Weather Service in Fort Worth, Texas, told CNN that areas with only a partial eclipse could see a slowing of the rise in temperatures from early morning to early afternoon.
A slowdown in temperature increases will limit the extent to which maximum temperatures can rise in the afternoon, potentially making Saturday a little cooler than it would have been without the eclipse. This could also happen in Dallas or Phoenix, where the moon blocks 80% of the sun.
Solar eclipses affect more than just temperature. Reduced solar radiation and cooler temperatures can also affect wind, humidity, and cloud cover.
Rapid cooling during a solar eclipse temporarily reduces the amount of heat stored in the atmosphere. The heat causes the air to rise, making the atmosphere unstable. The atmosphere then creates clouds, storms, and winds to release heat energy and try to restore balance.
Therefore, when the air is cooled by a solar eclipse, the atmosphere’s ability to balance itself is weakened, causing the atmosphere to become calmer and wind speeds to decrease.Scientists took many weather measurements in Wyoming and New York during the 2017 total solar eclipse And I found Wind speeds decreased by an average of 6 miles per hour as a result of the solar eclipse.
Perceived humidity is closely related to temperature. When the air temperature and the dew point, which measures the amount of moisture in the air, approach the same temperature, humidity increases. Therefore, when the temperature temporarily drops during the eclipse, the temperature tends to approach the dew point, making the air feel a little more humid.
If temperatures drop significantly, cloud cover may also change.
The 2017 total solar eclipse cleared the clouds above parts of South Carolina. This is because it has lost heat, the fuel that causes the air to rise and form clouds. Even if there is less of a drastic drop in temperatures, Saturday’s solar eclipse could also cause some clouds to disappear.
