EDS 221 Day 10 AM

Hurricanes and stream chemistry

August 21st, 2026

Hurricane Hugo

Study site: the Luquillo Experimental Forest

Photo: Erika P. Rodríguez / Audubon

Effects of the hurricane on streams

Schaefer et al. (2000) reported on the changes in stream water chemistry in the period following the hurricane.

In EDS 221, you will reproduce this analysis and others from the original study.

Smoothing with a moving average

Raw measurements, irregularly sampled, are noisy and confounding

Smoothed data reveal key patterns

Did you have an “a ha!” moment?

The path up to now

Remember where we started?

set.seed(123)
die <- 1:6
rolls <- sample(die, size = 2, replace = TRUE)
roll_total <- sum(rolls)


Since then we:

  • Made a kajillion concept maps
  • Sleuthed a hundred pages of code (maybe more?)
  • Gave/received a pep talk or three

What will you take with you?

Thank you!

The world’s greatest TA!

The Bren School staff


All of you!

If you only take away one thing…

This class was your first opportunity to learn computational thinking, not your only opportunity.

You’ll keep developing these skills for the rest of your career.

Schaefer, Douglas A., William H. McDowell, Fredrick N. Scatena, and Clyde E. Asbury. 2000. “Effects of Hurricane Disturbance on Stream Water Concentrations and Fluxes in Eight Tropical Forest Watersheds of the Luquillo Experimental Forest, Puerto Rico.” Journal of Tropical Ecology 16 (2): 189–207. https://doi.org/10.1017/S0266467400001358.