Decadal Trends in Lake Michigan Buoy-Measured Wind and Waves

Session: 32. - Long-Term Monitoring: Achievements, Challenges, and Solutions

Nicholas Olsen, Purdue University, [email protected]
Cary Troy, Purdue University, [email protected]

Abstract

Waves are a primary factor in beach health, sediment transport, and coastal erosion, the latter of which has been increasing along Lake Michigan's western coastline since 2014. While a primary factor in recent Lake Michigan erosion is undoubtedly increased lake levels, the recent erosion may be also indicative of changes in the lake's wind-driven waves. This study seeks to examine trends in Lake Michigan buoy measurements (NDBC Buoys 45002 and 45007) for the period 1980-present.  The buoys measurements generally span the months May-December.  The focus of this presentation is on long term trends in the magnitude and direction of Lake Michigan winds and waves, including extreme waves and storm events. Monthly-averaged wave heights are seen to be decreasing over the data set for all months, although not all trends are significant.  However, analysis suggests that since 1992 there has been a significant increasing trend in the mean height of waves approaching from the north at the lake's southern end during the months of June and July. Additionally, the last decade appears to have longer storm durations than the previous. Coupled with an increasing lake level since 2015 these trends could suggest an increase in wave energy directed towards the south.

1. Keyword
waves

2. Keyword
Buoys

3. Keyword
climatic data

4. Additional Keyword
coastal engineering

5. Additional Keyword
coastal processes

6. Additional Keyword
long-term trends