# Historical Temperature Records

Sarah Purkey; Surabhi Biyani; and Stephen Po-Chedley

## Overview

Climate change is experienced differently by people in different locations at different times. These experiences are directly connected to regional factors that determine temperature but also reflect how fast temperature is changing. In this lab, students graph and use basic statistics to analyze century-long temperature records from weather stations around the world and then look at modeled predictions of future temperature.  Students gain skills in data analysis, gain experience examining observational data as evidence of regional and global warming, and develop an understanding of spatial and temporal scales of climate variability. This module was originally developed by Sarah Purkey while she was a graduate student working on her Graduate Certificate in Climate Science at the University of Washington in 2012. Additional weather station data were added in early 2020 by Surabhi Biyani; Stephen Po-Chedley  knew how to grab the data from the NOAA website.  This material was designed to be part of a year-long High School Climate Science curriculum.  We have modified the lessons to be independent of the year-long curriculum, and recommend for use in high school courses including Statistics and Environmental Science.

Lesson 1: Seasonal Variability

Students pick a station (location)and make predictions about the region’s climate by calculating and plotting mean monthly temperature and examining variability within the monthly mean. As a class, share graphs and evaluate differences in regional seasonal variability.

Lesson 2:  Local and Global Historical Trends:

Students calculate the yearly mean at each station. As a class, compare yearly regional trends to IPCC trend maps.

Lesson 3: Climate Model Predictions and Local Impacts:

Students apply statistical tools learned in lesson 2 to model output for the next 100 years, then research and report on how the predictions for their region will impact  local communities.

## Focus Questions

1. How is climate change experienced in different parts of the globe? Variability can be thought of as differences between regions or differences within a region.  Consider how fast temperature is changing in one region compared to other regions (e.g. temperate vs. polar vs. tropics).  Consider how variable the climate can be in a particular region in a particular season.
2. What are surface warming trends in different parts of the globe.  How are they calculated?  How are these different from one another and from the global temperature trends?  Why are there differences?
3. How will local communities be impacted by climate change?  Explore this idea by considering how regional temperatures are predicted to change in the future.

## Learning Goals

Students will be able to:

1. Create and interpret time series from observed and modeled temperature data.
2. Plot and calculating trends, variance, means, and statistical error from raw data in Excel.
3. Be able to distinguish between local weather (regional variability) and global climate by examining short and long-term trends in temperature data

## Prior Knowledge (for students and teachers)

Students will perform some basic statistics on a real data set.  It is expected that students have some prior experience finding the average, standard deviation and linear line of best fit.

Students place their findings in the context of what they already know about weather, global variability of temperature and precipitation, and other factors influencing local climate such as proximity to water, latitude, and elevation.

Readings that help contextualize the data analysis are listed below for each lesson.  These readings are from Kump, L. R., J.F. Kasting, and R. G. Crane, The Earth System, 3rd Edition (hereafter referred to as Kump) and IPCC AR4  (https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-chapter11.pdf)

Lesson 1: Read chapter 4 of Kump.  Be familiar with basic excel functions including how to find the mean, variance, max, min, and standard deviation.

Lesson 2: Read chapter 15 from Kump and the IPCC report AR4 section TS.3 (https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-ts-1.pdf).

Lesson 3: Read chapters 15 and 16 in Kump and be familiar with the framework of Global Climate Models (GCM’s).  A good introduction to GCMs can be found in the IPCC AR4 Chapter 8 (https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-chapter8.pdf). For this lab, students are asked to read a section (10 pages or less) of the IPCC AR4 report describing the future predictions for a given region.  The sections discuss the weather phenomena affecting the different regions and how these will likely change. Students are expected to know basic large-scale atmospheric weather drivers. If they have questions, students can look up terms in Kump.

https://www.bloomberg.com/graphics/2015-whats-warming-the-world/

## Anticipated Challenges:

Students are expected to have some experience using Excel.  A number of online Excel tutorials can be found for students to do prior to this lab.   If students try to do the lab with no prior knowledge of Excel, they will spend a great deal of time working on Excel when they should be focused on thinking about the science.

As there are always hiccups in teaching with any software.  To minimize this the teacher should complete the lab (prior to having students do the lab) on the same version of excel used in the classroom .

## Materials:

• Computers with Microsoft Excel
• Temperature Data.  Open the “Historical Temperature Records” folder in the  UW PCC Google Drive Folder
• The folder “Station Data” contains observational data and model predictions for 18 different stations (xxxxx_obs.csv or xxxxx_model.csv where xxxxx=station number) through the year 2011 when this lab was originally created.
• “943260_example.xlsx” is an example file for station 943260 with figures generated (thru 2011).
• “New Station Data” folder contain station data (observations) through 2019.  The way weather stations are named in the database changed between 2011 and 2019.  Visit the “New Station Numbers” file for latitude, longitude, old station number, corresponding new station number and the time period represented in the data set (some weather stations go back further than others).
• The “Trend Figures” folder contains the final figures students generate in labs 1 and 2.
• global_temp.xls is a spreadsheet of global average temperature data for use in lesson 2.
• Worksheet template is a (.docx) file with notes for the instructor, but that can be converted to a student worksheet.

Please email uwpcc@uw.edu if you have any questions, and let us know how using the new data goes!

## Procedure:

#### Before the Lab:

Download Data: Station data needs to be downloaded for the students prior to the lab from the UW PCC Google Drive folder.   There is also an example spreadsheet with the calculations students will be asked to do (943260_example.xlsx). See the Materials section above for additional information on what is in this Google Drive resource.

The station files contain station location information and the monthly mean temperature over all years of observation recorded (or 100 years into the future for the model data) in degrees Celsius.

Edit Worksheets: The worksheets for each lesson are provided with notes for the instructor.  These need to be edited and tailored for your use.  Edit any instructions on how to navigate Excel so they apply to the version of Excel used in your classroom.

## One Approach. A Procedure for Teachers.

Lesson 1: Seasonal Changes.  Focus on a single month of data, from a single station see how it varies over time.  Compare with that from other locations.

1. Tell the students they will be working with raw data to determine the seasonal temperature cycle around the globe. (15 min)
1. Why do we have seasons?
2. How would you expect the surface temperature to change with latitude and why? Why would two cities at the same latitude, one on the east coast of the United States and one on the west coast of Europe have different climates?
3. Where on the globe would you expect large fluctuations between winter and summer temperatures and where would you expect small?
4. How would you expect surface temperature fluctuations to change with altitude?
2. Explain that the instrumental record is coming from weather station data. Volunteers have recorded temperature and precipitation daily at 1000’s of stations around the globe over the last 150 years.  NOAA has collected this data and made it available to the public.  Tell the students that today, they will each be given the temperature data for a station to work with.
1. Information on the data used for this lab can be found at: http://www.ncdc.noaa.gov/ghcnm/
2. Ask students: What kinds of things do we need to keep in mind when working with weather station data (have a discussion about missing data, spatial coverage, etc.)?
3. Tell students they will be studying data from a particular weather station and finding the climate, or climatology, for their region.
3. Hand out the Worksheet for Lesson 1. Divide students into groups, each must have their own computer with Excel. Assign each group a weather station.  Have students complete the first part of the Lesson 1 worksheet (30 minutes).
1. Have students open Excel and import their data.
2. Have the students work through Parts I-III of Lesson 1.
• Teachers should be circulating around the classroom to make sure students are progressing and not getting stuck on something in Excel.
• Students discuss the questions as a group and individually write up short answers.
• Students print out the final figure from Part III.
4. Have students proceed to Part IV of the lesson. (20 min)
1. Have each group pin up their plot with a string.
2. Allow students to circulate and look at all the graphs. Have the students go back to their groups to discuss the part IV questions and individually write up short answers.
5. Bring the class back together for a discussion. (10 min)
1. Ask the students to discuss the differences between the plots generated by the different groups. Discuss the differences in climatology around the globe and ask the students why they think some areas might differ.
2. Discuss data and noise. Ask the students if there was anything they found surprising about working with raw data.

Lesson 2:  Calculate annual average temperature and see how that has varied over time at a single station.  Compare with that from other stations.

1. Tell the students they will be working in teams to discover trends in climate around the globe. (10 min)
1. Ask students: How do we know about past changes in climate? Discuss time scales. If paleoclimate has been covered start with a recap of methods for knowing long term variability. Then ask how we know about the last 100 years? Last 20 years?  Yesterday? How does the precision and accuracy of our knowledge of past temperatures change as we get closer to today?
2. (If you have done Lesson 1 you’ve already talked to the students about the data set and can skip some of this;  groups and stations can be the same as used for the previous lesson). Tell students that the instrumental record is coming from weather station data. Volunteers have recorded temperature and precipitation daily at 1000’s of the stations around the globe over the last 150 years.  NOAA has collected this data and made it available to the public.  Tell the students that today, they will each be given the temperature data for a station to work with.
3.  Ask students: What kinds of things do we need to keep in mind when using weather station data (have a discussion about missing data, spatial coverage, etc)? Ask students about collection methods and accuracy (e.g. 100 years ago vs. today when air temperature can be measured are recorded every minute electronically).  Briefly touch on data collection and human error.
4. Tell students they will be researching the region for their particular weather station and looking at the quality of the data set.
2.  Hand out the worksheet for Lesson 2. Divide students into groups, each must have their own computer with Excel. Assign each group a weather station.  Students complete the first part of the worksheet (30 minutes).
1. Students open Excel and import their data.
2. Students work through Part 1 of Lesson 2. Have the students print out their final figures.
3. Students discuss the Part I questions as a group and individually write up short answers.
3. Have students do part two of the lesson (20 minutes)
1. Have each group pin up their plot with a string.
2. Allow students to circulate and look at all the graphs. Have the students discuss the part II questions as a group and individually write up short answers.
4. Have students complete part three of the lesson (20 minutes)
1. Students go back to their computer work stations with their group.
2. Students import global data (‘global_temp.xls’).
3. Allow students to work through part III of the lesson and answer questions.
5. Bring the class back together for a discussion (10 min)
1. Ask the students to discuss the differences between the plots generated by the different groups. Discuss the differences in global trends and ask the students why they think some areas might warm more than others.
2. Discuss the global trend. Ask students to explain different aspects of the plot (ie, the different trends, smoothed line, dots) to reiterate what they just learned.
3. Ask the students why they think it is important to look at both regional and global trends.

Lesson 3:  Explore model projections of temperature.

1. Tell the students they will be working in teams to study future climate projections. (10 min)
1. Ask students and discuss: What is a climate model? What can they be used for ? (one answer: to look for possible responses of a system to change) What are GCMs (Global Climate Models)? What are the different “carbon scenarios”?
2. Additional information can be found in chapter 8 of the IPCC AR4 report (https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-chapter8.pdf)
2. Explain to the students that there are many different GCMs and today they will be looking at data from a GCM developed by the Geophysical Fluid Dynamic Laboratory (GFDL) located in Princeton, N.J. They will be looking at data produced under the A2 scenario. They will be receiving data for their station.
1. Addition information on the GFDL GCM can be found at:  (http://www.gfdl.noaa.gov/model-development)
3. Hand out the Worksheet for Lesson 3. Divide students into groups (perhaps the same groups as you had in Lessons 1 and 2), each must have their own computer with Excel. Assign each group a weather station (these groups and stations can be the same as used for the previous two lessons).  Have students complete Part 1 of the worksheet (30 minutes).
1. Students open Excel and import their data.
2. Students work through Part 1 of lesson 3 and print out their final figures.
3. Students discuss the part I questions as a group and individually write up short answers.
4. Have students do part II of the lesson either in groups in class or as homework.
1. Pass out a copy of chapter 11 of the IPCC Working Group I “The Physical Science Basis” (https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-chapter11.pdf).
2. Students should read the section of the report that contains information about their individual station (4-10 pages).
3. The lesson provides some leading questions to be considered but the format of this is left fairly open. Students should pick a topic they think is the most interesting to write up about climate change in their regions.
4. Report should include facts about predicted and temperature changes in their region taken from the IPCC report and include facts about the current economic (including agricultural) conditions.  Past this, the report can be highly speculative with no right or wrong answer. The students are simply asked to think about the societal impacts of the predicted climate change.
5. **NOTE** Teachers should decide how much time they want students to spend on this project outside of class and give students a page max if they are asking for a formal written report. I would suggest two signal spaced typed pages (roughly one page summarizing the predictions made in the IPCC report and one page discussing the impacts on local communities.  The later part will be highly speculative so should be easy for students to write.  Teachers should emphasize that this part of the project can be their educated guess and they do NOT need to research other published opinions).
• An alternative to individual reports, each group could give a 15-20 minute presentations.

Weather Stations

IPCC report

Similar data analyses activities can be found at:

Attribution:  Purkey, S., Biyani, S., and Po-Chedley, S., “Historical Temperature Records” Climate Science for the Classroom edited by Bertram and Biyani, 2020. https://uw.pressbooks.pub/climate/chapter/historical-temperature-records Date of Access.