Latitude & Climate
Lesson 1 of 9
Objective: SWBAT identify the relationship between latitude and planetary temperature and precipitation rates
This unit introductory lesson asks students to do a few things. First, and most importantly, it's critical that students learn about the relationship between climate and latitude. This relates back to the previous unit on Insolation, but this principle will introduce the various ways in which climate is affected by movements and processes of the Earth. After an introductory reading and some key information, students practice what they've learned on some Regents-based problems that address this exact standard. As a note, there are no special materials needed for this lesson, although I would highly recommend you have a color copy of the 'World's Deserts' image (which is the lesson image above, and also included as a resource below) so that students can more easily differentiate between the two colors
[Note: For embedded comments, checks for understanding (CFUs), and key additional information on transitions and key parts of the lesson not necessarily included in the below narrative, please go to the comments in the following document: 6.1 - Latitude and Climate (Whole Lesson w/comments). Additionally, if you would like all of the resources together in a PDF document, that can be accessed as a complete resource here: 6.1 - Latitude and Climate (Whole Lesson)[PDF]. Finally, students may need their Earth Science Reference Tables [ESRT] for parts of the lesson (a document used widely in the New York State Earth Science Regents course) as well.]
Students come in silently and complete the (attached) Do Now. In this case, the Do Now is a review of material and some "hot standards" from earlier units. After time expires (anywhere from 2-4 minutes depending on the type of Do Now and number of questions), we collectively go over the responses (usually involving a series of cold calls and/or volunteers), before I call on a student and ask them to read the objective out loud to start the lesson.
As a general note, the Do Now serves a few purposes:
- It serves as a general review of the previous day's material;
- It is a re-activation of student knowledge to get them back into "student mode" and get them thinking about science after transitioning from another content area or alternate class;
- As a strategy for reviewing material students have struggled with (for example, using this as a focused review for material that they have struggled with on unit assessments or recent quizzes); and,
It is an efficient and established routine for entering the classroom that is repeated each day with fidelity (I never let students enter the classroom talking. While it may seem potentially severe to have students enter silently each day, this is both a school wide expectation and a key component of my classroom. In many respects, I find that students readily enjoy the focus that starting with a quiet classrooms brings each day).
Since this lesson re-introduces earlier topics of latitude, I want to give students a brief re-activation on major lines of latitude. In the Latitude Activity, I take a brief few seconds to introduce the new unit as a continuation of looking at the atmosphere (from the previous unit's coverage of Meteorology), but one that will expand on some key concepts and ideas learned previously. I then ask students to take a minute or so and, using the provided map of the Earth, draw the associated lines of latitude that are bulleted on the Latitude Activity resource. I ask students to do this for about 40 seconds independently, before giving them the chance to check their work with a seat-mate. Then, we circle back whole class and quickly go over the responses collectively (Hint: The actual lines are given in a very tiny font on the actual map. If you look closely, or you zoom in with a document camera, the lines should be easier to see.)
Introductory Text & Activity
After the re-activation activity with latitude, we introduce the main concept through the Introductory Text & Activity resource, which is that latitude and climate have an interestingly complex relationship. First, there is the notion that as latitude increases (moves toward the North & South Poles), that temperature goes down. This is a function of the lessening intensity of insolation via Earth's tilt and orbit around the Sun. Conversely, the relationship between latitude and precipitation is much more nuanced. Precipitation doesn't follow a purely direct linear relationship, but is the result of specific climate belts that appear due to Earth's rotation (the Coriolis Effect, which they've learned about here).
Using our favorite reading strategy, our Control The Game reading (where I popcorn around the room at random times, calling on students to read out loud), we read the first page of the Introductory Text, which discusses the above mentioned relationship between latitude and temperature (Note: The annotated lesson comments are particularly helpful here in providing some key information and Checks for Understanding [CFUs], so please reference the Entire Lesson Word document in the Lesson Introduction section above). At the end of the class reading, I give them just a few seconds to answer the Stop + Jot question at the bottom of the page, which summarizes the basic relationship between latitude and temperature.
On the second page of the Introductory Text, which asks students to discuss the relationship between latitude and precipitation, I ask students to do much the same thing we did on the first page, but with a partner. Their task is to collectively read (I let them decide on how to read - out loud, silently and then discussing, etc.) and then answer the associated Stop + Jot question at the bottom of the page. As a note on the Stop + Jot question, you can have them reference the Earth Science Reference Tables [ESRT][Page 14] if they're really struggling. Also, check out the reflection in this section for more context here.
The final thing we approach in this section is the same lesson image you'll see at the top of this webpage, and one I find really fascinating. The image is a satellite-based image that has had the clouds digitally removed, showing the relative features of the Earth as seen from space. The two maps show major areas of Earth's biomes! For more info, the top image shows the areas of Earth's major desserts, which happen to match up really well at the dry areas of 30 degrees N/S. Conversely, the bottom image shows the major rainforests of the world, which all appear right around or along the Equator, where a major belt of precipitation is located! If the students need it, I give them a hint to draw out the lines of latitude, (30 degrees N/S on the top image, the Equator [0 degrees] on the bottom image), but it usually takes them a while to get what these images are about.
The Practice section in this lesson is, like the vast majority of questions found in all of my classwork and homework, is 100% Regents-based. All of the questions come from prior Regents examinations. Likewise, as I try to generally do with all of my lessons, the questions are mostly organized to get increasingly more difficult and increase in complexity, which is why the harder questions tend to come toward the end.
In terms of student work habits, I tend to sometimes make this decision in the moment, and as a response of what I know about the students and how they're processing the material on, but I'll either ask them to work independently, in partners, or (sometimes) give them the option. Usually, before starting practice, we tend to go over some steps for self-help ("What should you do if you're stuck?"), and I might reference a previously used multiple-choice or free response strategy in order to build their skills while simultaneously learning content (as an example - one popular one we always use - "If you aren't sure what the right answer is, see if you can eliminate some wrong answer choices"). I tend to circulate for compliance and then hone in on specific students while they're doing this.
After about 10 minutes, we go over their responses. Students who finish early are encouraged to work on the exit ticket (resource below) and double-check their responses. We use a combination of strategies (active voting, cold calling, popsicle sticks, volunteers) to go over the responses, where students correct their work and ask any clarifying questions.
Exit Ticket & Closing
In the last few minutes of class, I have students complete the daily Exit Ticket. For the sake of time, I have students grade them communally, with a key emphasis on particular questions and items that hit on the key ideas of the lesson (Note: This usually manifests as students self-grading, or having students do a "trade and grade" with their table partners). After students grade their exit tickets, they usually pass them in (so that I can analyze them) and track their exit ticket scores on a unit Exit Ticket Tracker.
After students take a few seconds to track their scores, we usually wrap up in a similar way. I give students time to pack up their belongings, and I end the class at the objective, which is posted on the whiteboard, and ask students two questions:
- Do you feel that you mastered the objective for the day?
- Can you reiterate one thing you learned about (in this case, asking students to describe the relationship between latitude and climate, etc.)?
Once I take 2-3 individual responses (sometimes I'll ask for a binary "thumbs up/thumbs down" or something similar), I have students leave once the bell rings.