We often hear the phrase “Pabago-bago ang isip, parang panahon,” when referring to someone who is being fickle-minded or indecisive. This is because weather could change easily and in a short period of time
But what really influences sudden changes in the weather? In the last column, we learned about weather parameters. Today, we would be sharing about weather systems and patterns, knowledge of which would help best prepare you for the vagaries of day-to-day weather conditions.
According to the National Oceanic and Atmospheric Administration (NOAA), the Earth’s weather would be completely different had it been completely motionless, with a flat dry landscape, and an un-tilted axis. However, this is not the case and we only have what we currently have — local and global weather conditions that are highly susceptible to sudden changes. NOAA further states that local weather that impacts our daily lives results from large global patterns in the atmosphere caused by the following:
There are temperature differences in different places around the globe because of uneven solar heating between regions. This is mainly caused by high and low pressure areas that develop globally. Meanwhile, the horizontal movement of heat by wind from lower to higher latitudes is strongly affected by the Earth’s rotation. This stops the wind from directly flowing from a high-pressure zone to a low-pressure zone, and instead, wind flows around high and low pressure centers.
As uneven heating is everywhere, it produces global circulation patterns. In this case, the large quantity of energy reaching the equator produces hot, humid air — making these regions relatively warmer than other parts of the globe.
Global winds result in large bodies of air that are known as air masses. These are thousands of feet thick and extend across large areas of the Earth. As they develop in different areas, their location of origin basically identifies their characteristics.
In the case of air masses over tropical oceans, they become excessively hot and humid. Meanwhile, air masses over high latitude areas tend to be cold and dry.
Now that you know air masses, you will easily remember that whenever two air masses meet at a specific location, that area becomes a front. There are two main types of fronts, namely cold fronts and warm fronts. A cold front is where a cold air mass replace a warm air mass. If it is otherwise–when warm air replaces cold air–then it is considered a warm front.
Air masses and fronts are two factors that affect the local weather conditions that we experience daily. While these two directly affect our weather patterns, the environment in the higher parts of the atmosphere impacts the movement of air masses and fronts. Up there, narrow bands of strong winds, such as jet streams, control and affect weather systems. They are also responsible for the movement and transfer of heat and moisture around the globe.
There are two types of heat transport: vertical and horizontal heat transport. Vertical heat transport involves the heating of the Earth’s surface and the development of vertical air currents. This leads to the development of puffy-looking clouds, showers, and thunderstorms to form in warm air masses.
Meanwhile, horizontal heat transport originates from the Earth’s spherical orientation where the Earth receives more sunlight (ergo warmer conditions) in the tropics, and less sunlight toward the Northern and Southern Poles. This results in horizontal differences in temperature, which then leads to air pressure differences. Given this, wind eventually transports heat from the tropics to high altitudes.
Together, these two cause uneven heating in both horizontal and vertical directions in the atmosphere, and results to the changes we perceive as “weather”.
Relevance of Knowing Weather Patterns
It is important to note that the weather patterns and events that we experience are not assigned randomly; instead, they are based on scientific processes unlike superstitious beliefs such as offering eggs to achieve good weather.
For better decisions in the future, it is best to consult reliable weather information from dependable weather organizations such as the state weather bureau and private weather providers like WeatherPhilippines.
Whether you’re staying indoors or going out this weekend, don’t forget to stay #WeatherWiser!
Interested about being #WeatherWiser? Contact us at firstname.lastname@example.org.
–By Josa Marie Salazar
Sustainability Specialist, WeatherPhilippines Foundation, Inc.