# Use Time Series Data in R and Python to Understand Change: Lessons

Time series data are used to understand changes over time in our environment. For instance, you can collect temperature data over time to track how temperature fluctuates, hourly, daily monthly and even annually. However often working with dates and times in tools like R and Python can be tricky given different date and time formats and time zones. Learn how to work with, clean up and plot time series data in the R programming language in the lessons below. Stay tuned for Python lessons!

## Subset & Aggregate Time Series Precipitation Data in R Using mutate(), group_by() and summarise()

This lesson introduces the mutate() and group_by() dplyr functions - which allow you to aggregate or summarize time series data by a particular field - in this case you will aggregate data by day to get daily precipitation totals for Boulder during the 2013 floods.

last updated: 10 Jan 2018

## Homework Challenge: Plot USGS Stream Discharge Data in R

This lesson illustrated what your final stream discharge homework plots should look like for the week. Use all of the skills that you've learned in the previous lessons to complete it.

last updated: 10 Jan 2018

## Summarize Time Series Data by Month or Year Using Tidyverse Pipes in R

Learn how to summarize time series data by day, month or year with Tidyverse pipes in R.

last updated: 10 Jan 2018

## Use Tidyverse Pipes to Subset Time Series Data in R

Learn how to extract and plot data by a range of dates using pipes in R.

last updated: 10 Jan 2018

## Time Series Data: Work with Dates in R

Times series data can be manipulated efficiently in R. Learn how to work with, plot and subset data with dates in R.

last updated: 10 Jan 2018

## Explore Precipitation and Stream Flow Data Using Interactive Plots: The 2013 Colorado Floods

Practice interpreting data on plots that show rainfall (precipitation) and stream flow (discharge) as it changes over time.

last updated: 10 Jan 2018

## Work With Precipitation Data in R: 2013 Colorado Floods

Learn why documentation is important when analyzing data by evaluating someone elses report on the Colorado floods.

last updated: 10 Jan 2018

## Use Google Earth Time Series Images to Explore Flood Impacts

Learn how to use the time series feature in Google Earth to view before / after images of a location.

last updated: 10 Jan 2018