What does the spacing between isobars on a GFA represent in terms of pressure?

The spacing between isobars on a Graphic Flight Analysis (GFA) chart indicates the pressure gradient, which is crucial for understanding wind speed and potential weather developments. Specifically, a closer spacing of isobars denotes a steeper pressure gradient, resulting in stronger winds.

In the context of the choices provided, the standard spacing for isobars on GFA charts is typically set at intervals of 4 hPa. This standardization allows for consistent interpretation of weather data, providing pilots and meteorologists with valuable information on wind and pressure patterns. Recognizing this interval helps users gauge the relationship between pressure differences and anticipated wind strength, which is vital for flight planning and safety.

It’s worth noting that while other options suggest different values for isobar spacing, the accepted interval of 4 hPa aligns with established meteorological conventions, reinforcing why this choice is the correct one.