# Dress for Winter

### Overall Rating

Subject:
Chemistry, Climate
Duration:
40 - 50 minutes
Group Size:
Up to 24
Setting:
indoors or outdoors
National/State Standards:
Wyoming State Standards - Science
SC8.1.3
SC8.1.5
SC8.1.11
SC8.1.13

Common Core
English and Language Arts
CCSS.ELA-Literacy.W.5.4
CCSS.ELA-Literacy.W.5.2

Mathematics
CCSS.Math.Content.5.NBT.B.7

Next Generation Science Standards
5-PS1-3
5-LS2-1

### Overview

Students will dress for winter while explaining the purpose and function behind each layer. Throughout the lesson, students will learn and incorporate vocabulary terms related to heat transfer. At the completion of the lesson, students will be able to explain the different clothing layers and make reasonable choices for dressing in winter conditions.

### Objective(s)

1. Students will be able to choose appropriate clothing for outside winter activities.
2. Students will identify the 3 clothing layers needed for outdoor winter activities and explain why each layer is necessary.
3. Students will be able to define the terms conduction, radiation, respiration, evaporation and convection, citing specific examples in Grand Teton National Park.

### Background

Winters are long and cold in Jackson Hole. The first heavy snows fall by November 1 and continue through April; snow and frost are possible any month. At park headquarters, snowfall can average 14 feet in a season. In the mountains, snowfall can average 33 feet. Between winter storms the days are sunny and the nights are frigid. From December through February the average high temperature is 28°F and the average low temperature is 2°F with lows as low as -30°F.

Heat is lost from the body in five ways. It is radiated from the body in the form of infrared radiation. It is lost through convection as the air immediately adjacent to the body is warmed and then disturbed by wind. It is similarly lost through respiration as cool air is taken into the lungs, warmed and then exhaled. Heat loss also occurs by conduction when the body comes in direct contact with some cooler surface, such as the ground, cold pots, snow, rocks, etc. And finally, heat is lost when moisture on the body's surface evaporates - an exothermic chemical reaction. Because an active snowshoer, skier, or hiker can sweat four to six liters of perspiration in a day, evaporative heat loss has special implications for clothing selection. In order to prevent radiation and conduction, some clothing articles must be capable of providing the wearer with "insulation," a thermal barrier of trapped dead air space that conducts heat away from the body as slowly as possible. Because the body and outdoor elements are continuously exposing insulating clothing to moisture, it is a valuable asset for clothing to insulate even when it is wet.

### Materials

Materials will be brought in by the teacher prior to the lesson. The materials will mostly consist of synthetic, down and wool clothing layers for outside recreation. The clothing should be consistent for a layering system that would be appropriate for winter travel in the Tetons.

Synthetic clothing layers for upper and lower body - the materials will visually demonstrate the purpose and function of each layer. Each layer will build upon and compliment the previous layer.

Synthetic/wool outer body pieces - gloves, hat, boots. These materials will visually demonstrate their function.

### Assessment

-Students will list and describe the five main means by which we lose heat from our bodies in the winter.

-Students will list and describe the three main clothing layers and each of their respective functions.

-Students will be able to discuss/explain winter weather, and factors for consideration when dressing for outdoor activities in Grand Teton National Park.

### Park Connections

The lesson relates outdoor preparedness to the dramatic winter weather of Grand Teton National Park. In order to safely enjoy and explore the outdoors, students need to have the understanding that clothing can wick, insulate, and transfer heat energy.

### Extensions

The teacher could wear or demonstrate with a wet synthetic sock and a cotton sock and record the temperature and/or time it takes each one to dry.

You could have the student models (while dressed in all their layers) step outside for 30 seconds and come back inside to report their experience to the class.

Depending on the group size and the materials available, the facilitator could bring in many different duffle bags and have the students break into small groups to dress up their classmates.

*Winter adaptation extension – Students could compare/contrast the inability of people to adapt to winter and our subsequent need to layer our clothing, to the abilities of other animals in Grand Teton National Park that cope with winter by growing thicker coats, hibernating, migrating, etc.