Discussion of Results

Discussion of Results

From the results we can see several important things including the reason for the waves, the weather conditions that lead to the best surfing, and the changing of wave height trends with the changing of the seasons.

In order to be a good surfing wave, a wave must be a minimum height and be able to break at this height. The actual minimum height is debated among surfers of various abilities, but it seems to be generally agreed upon that a 3 foot height should be the low end to shoot for. Of course, the higher the wave the better, particularly if they are able to break at larger heights.

The first result we will discuss are the properties of this particular bay that make it so popular as a surfing destination. Several reasons are obvious such as the new harbor and marina nearby and the proximity to the city of Sheboygan. Beyond this, the major draw is the waves that are created coming into the bay. After delving into the factors contributing to these waves, it becomes evident that there are several reasons behind the occurrence. When high speed winds are able to come from the east to north east the fetch is long enough that the wind from these directions provides a significant amount of energy to create waves. The other major advantage that this site has is the slope of the bottom leading up to the shore. Slightly offshore, the bottom begins to slope at a higher than usual rate which leads to two key elements of creating good surfing waves. The bottom allows for the creation of large waves in a short time span, as well as causing these waves to break at larger heights, leading to ideal surfing conditions.

The next question that was investigated was the wind speed and direction that produced the ideal surfing conditions. The results show that there isn’t one specific perfect condition, but there are definitely noticeable trends. In general, wind from the north and northeast created the best waves. This makes sense taking into account what we have learned in class regarding wave height and its relationship to wind fetch. Furthermore, a wind speed of between 12-15 meters/second is the lowest amount of wind needed to produce decent waves for surfing.

The last question to be investigated was the popularity of winter surfing. Was there a reason that so many people braved the frigid water during the coldest months or was it just foolish bravado? After separating data sets for winter and summer months, we see that there is a slight difference –about .2 meters - between each of the average wave heights. It is difficult to determine if this difference is significant enough to say for sure that it will always happen, especially since there is so much variation in the amongst the months themselves. If we assume that this is a significant difference, the explanation for this occurrence I believe lies in the water level fluctuations. When the water level drops this, in effect, causes the water to move out towards the lake. Since the lake begins to slope more steeply as it get deeper, this causes the waves to hit the steeper slope closer to the shore. The combination of these two factors provides a plausible explanation of the winter effect we are seeing.

In order to determine if a set of weather conditions is good for surfing, a simple application of the JONSWAP method will be accurate enough to provide correct results. Use the included estimation table for fetch values and a few simple calculations will help any potential surfer determine if the waves will be good that day.

The results and conclusions drawn from this project are only estimates based on historic data but they seem to help show why surfing in Sheboygan Harbor has become such a popular hobby. Several assumptions were made when manipulating the data, so the results may lack some precision but the general trends shown can not be ignored. All of the natural conditions at the Sheboygan Harbor contribute to making it the place to be for surfing in Wisconsin.