Earthquakes, Fires, and Mudslides. The Community Selected

¶ … earthquakes, fires, and mudslides. The community selected for this activity is San Diego, California, and area regularly experiencing natural disasters of often high magnitude. This module will be a Hazard analysis of each disaster. Fires: Brush fires are by far the greatest threat to San Diego and its surrounding communities. San Diego's brush fires have a consistently catastrophic magnitude, burning everything in their paths.

This disaster has a frequency of highly likely, as there have been fires every year in San Diego county for the past ten years (Preventing and Preparing for Brush Fires). San Diego brush fires do have a seasonal pattern and occur consistently in the months of August through October during the dry season. Additionally, these months are the months of the Santa Ana winds that spread the fires quickly causing even more damage to forests and homes in the area.

The duration of brush fires has been as long as an entire month as fire fighters work to contain the damage. Brush fires have a minimal speed of onset especially in areas with thick, dry brush. Often something as small and insignificant as a discarded magnifying glass can result in a catastrophic fire within hours. This emergency has top priority for the San Diego community as its destruction is so immense and the danger so great. Mudslides: Mudslides are the next greatest threat to San Diego residents.

Mudslides have a limited magnitude destroying primarily property. Mudslides are likely to occur in San Diego following any brush fire (San Diego News, 2004). After a brush fires occurs, the ash and loose top soil easily become mud during the rainy winter season. Because there is no living brush to hold the soil in place and due to the mountainous environment, the mud travels down the mountains at alarmingly high rates, wiping out homes, buildings, and vehicles in its way.

Mudslides to a particular area can happen up to two years after the actual fire causing a clear seasonal pattern that follows seasonal fires. The duration of mudslides is very short, lasting only hours but doing serious damage. Unlike fires, mudslides do provide at least a 24-hour warning to residents. As meteorologists detect heavy rains approaching, decisions can be made to evacuate potential mudslide areas to keep residents safe. Earthquakes: California is on the San Andreas fault line. This means that earthquakes are a common occurrence (Azpiri, 2010).

The magnitude, however, for most earthquakes in negligible; however trends are showing an increase in earthquake intensity raising the magnitude concern to limited (NEIC, 2012). Earthquakes are highly likely to occur in San Diego, with multiple earthquakes happening each year. There is no seasonal pattern.