We have previously discussed the movement of air around the Earth, and the circulation pattern called the Hadley cells. Another important factor in Earth’s climate is Rossby waves.
Because the equator is hot, heated air rises and moves away from the equator, dropping its moisture as it cools. At about 30 degrees latitude, the now dry air falls back to the Earth, producing deserts. As the air reaches Earth’s surface, it moves north and south, creating the trade winds in the subtropical area and the prevailing mid-latitude winds in latitudes between 30 degrees and the polar regions.
A wide range of things alters this simplified picture. When greenhouse gases like carbon dioxide accumulate, they reflect infrared radiation causing the Earth’s atmosphere to become hotter. This effect isn’t uniform, however. Because of melting sea ice, Earth’s poles are affected by greenhouse gases more than the area of the equator. This causes a thermal imbalance between the poles and the equator affecting circulation around the poles and creating Rossby waves.
As the thermal imbalance has become greater and the air more wobbly in recent years, that affects the jet stream. The wobbles this past year have caused the northern jet stream to go further south than usual, bringing cold into Arizona in late spring. When the jet stream swung north, it brought hot tropical air toward the poles. On its way north, it brought unusual amounts of water into Oklahoma while Anchorage, Alaska, got temperatures over 90 degrees for the first time ever. Rossby waves is the name applied to the meandering high-altitude winds that have a major influence on Earth’s weather.
All of this shows us how fragile Earth’s climate is. Weather patterns depend on a wide range of variables which include the:
*size of the Earth’s atmosphere
*tilt of the Earth
*distribution of land compared to water
*chemical makeup of the atmosphere
*kind of radiation coming from the Sun and how that radiation is absorbed and reflected
*nature of Earth’s surface (whether ice or black dirt)
All of those factors go into making Earth a habitable planet.
We exist on this planet because of the precision design and construction of Earth and its atmosphere. The fact that it has stayed stable long enough for human life to exist for thousands and thousands of years is a testimony to the careful design and construction. Proverbs 8 finds “wisdom” speaking about its role in the creation process. Wisdom says she was there before the creation (verse 22-23) and that wisdom was a part of the preparation of the heavens (verse 26-28).
As we see the results of the small changes that have happened to the atmosphere in the past 100 years and the instability of Rossby waves, we wonder at Earth’s design and the wisdom of God who created it.
— John N. Clayton © 2019
Reference: Astronomy, December, 2019, page 64.