Weather & Pollution

Temperature Gradient and Altitude Changes

• Normal Lapse Rate: The average normal lapse rate is $6.5^{\text{o}}C$ per $1,000$ meters.

  • This indicates that for every $1$ kilometer ($1,000$ meters) increase in altitude, the temperature decreases by approximately $6.5^{\text{o}}C$.

• Example of Elevation and Altitude:

  • Standing at Earth's surface and ascending $1,000$ meters results in an altitude difference.

  • This equates to about $100$ feet, which is $1/10^{\text{th}}$ of $1,000$ feet.

• Temperature Expectation from Altitude Change:

  • With no airflow or other conditions, a change of $100$ feet in elevation results in an expected temperature difference of roughly $0.36^{\text{o}}F$ (or a little less than half a degree Fahrenheit).

Atmospheric Layers: Troposphere and Stratosphere

• Troposphere:

  • Extends approximately the first $12$ kilometers (or $7.5$ miles) above Earth's surface.

  • Contains about $80\%$ of the atmosphere's mass, indicating that most air molecules are within this layer.

  • This layer is crucial for weather phenomena including clouds, rainfall, and snowfall.

  • Defined by strong vertical mixing, where air molecules may move vertically.

  • Example: Development of thunderstorm clouds visualized as tall cumulus clouds.

• Boundaries in the Atmosphere:

  • The boundary of the troposphere is known as the tropopause where temperature changes characteristically cease to drop with altitude.

Importance of Meteorological Data Collection

• Role of Data in Weather Modeling:

  • Meteorological data is critical for accurate weather prediction and safety in aviation, as the National Weather Service operates under the Department of Commerce.

  • Weather stations are typically located at airports due to their critical role in transportation and weather forecasting.

• International Data Sharing:

  • Countries exchange meteorological data and weather models to improve local forecasts, considering that weather patterns can be influenced by neighboring regions.

Temperature Inversions

• Definition: A temperature inversion occurs when warmer air sits above cooler air instead of the typical pattern of cooler air sitting underneath warmer air.

• Example: In Minnesota, when warm air moves in and creates conditions favorable for thermal inversions, leading to the formation of fog.

Stratosphere Overview

• Location: The stratosphere lies $12$ to $15$ kilometers above Earth's surface, typically characterized by fewer clouds and generally horizontal airflow.

• Ozone Concentration: The stratosphere is notable for containing the base concentration of ozone, which acts as a protective layer against harmful ultraviolet radiation.

  • The distribution of ozone is plotted on a graph, where the concentration of ozone increases with altitude in this layer.

Impact of Stratospheric Phenomena on Weather

• Stratospheric Disruptions: Occasionally, disturbances in the stratosphere can influence surface weather patterns, particularly near the poles. Such disruptions can lead to unusually warm conditions in typically cold regions, as seen in climate anomalies.