Several notable weather patterns and atmospheric conditions characterize the beginning of an ice age:
Cooling Trend: The overall trend during this period is a sustained decrease in temperature. The cooling process can span thousands to tens of thousands of years, gradually changing the climate from warm or temperate to colder conditions.
Changing Precipitation Patterns: As the climate cools, the amount and distribution of precipitation change significantly. Some areas may experience increased snowfall, while others might face decreased rainfall or altered rainfall patterns.
Reduced Evaporation: Lower temperatures lead to a reduction in evaporation, affecting the hydrological cycle. With less moisture evaporating from the surface, atmospheric humidity levels decrease.
Increased Storminess: The cooling atmosphere can trigger more frequent and intense storms, including blizzards, heavy snowfall events, and cold fronts. These storms contribute to the accumulation and persistence of ice and snow.
Altered Wind Patterns: Changes in atmospheric circulation can result in shifts in prevailing wind patterns. These changes can have localized effects on temperature and weather conditions in different regions.
Glacier Formation and Expansion: As temperatures drop and snowfall accumulates, glaciers begin to form and expand in polar and high-altitude regions. These growing ice masses further contribute to the decrease in global temperatures.
It's important to note that the transition to an ice age from warmer climatic conditions is a gradual and complex process that involves numerous interacting factors. The specific weather conditions and patterns at the beginning of an ice age can vary depending on regional variations and geographical locations.