Which of the following factors does NOT typically affect the downwind dispersion of a gas release?

The factor that does not typically affect the downwind dispersion of a gas release is the type of ground cover. In atmospheric dispersion modeling, the primary elements that influence how a gas spreads through the air include wind speed, release height, and gas density.

Wind speed is crucial because it dictates how fast the gas will be transported away from the source. Higher wind speeds generally lead to a quicker dispersion of gases over larger distances.

Release height is significant as it influences where the gas enters the atmosphere, which can impact its subsequent dispersion patterns. A higher release can allow the gas to travel further before it is affected by ground-level factors, leading to a broader dispersion.

Gas density also plays a role because it determines how the gas behaves in the atmosphere. Lighter gases tend to rise, leading to different dispersion patterns compared to heavier gases that may sink or spread along the ground.

In contrast, while type of ground cover can affect local turbulence and the behavior of gases close to the ground, it is not a primary determinant of how gases disperse downwind. Factors that affect the movement of gas dispersal are predominantly related to atmospheric conditions and the characteristics of the gas itself rather than the immediate surface conditions. Thus, the type of ground cover does not have