FIX! ESCI D.S5.O1.A5 Feedback Loops

Intro  to  Feedback  Loops    

Introduction:  The  dynamic  changes  that  take  place through  interactions  of  the  geosphere,   atmosphere,  hydrosphere  and  biosphere  can  be  better  understood,  modeled  and  predicted   through  the  use  of  feedback  loops.  In this activity,  you will  learn what  a  feedback loop  is and how they  are used.  Let's  begin with  the concept  of equilibrium.    Equilibrium can  be defined  as a  system in  balance when the  inputs and  outputs do not  vary over  time.    If something  is in  a   state of equilibrium  it is  stable but  not unchanging.    When nature  is left  to itself,  it often   reaches equilibrium,  at least  until the  next volcano  or ice  age arrives.    These events  are actions.   People also  create the  “action”  when we  alter natural  systems.     The action  is often  followed by  an  “effect”.    Think of  what would  happen if  you reached  over and  poked the  person next  to you.    What effect  would you  expect this  to have   on that person?    Scientists call the reaction “feedback” and  it  can  be  negative  or  positive.    Do  not  let  these  terms   fool  you,  they  may  only  be  positive  or  negative  depending   on  your  point  of  view.     Lets  say  the  person  next  to  you  yells  and  calls  the  teacher   over  to  report  your  misbehavior.    You  promise  not  to  poke  anyone  again.    This  would  be  an   example  of  a  negative  feedback  loop  because  the  feedback  reduces  the  action  in  the  future.   A  positive  feedback  loop  increases  the  likelihood  of  the  action  to  occur  again.    Often,  in  a   system  negative  feedback  loops  help  to  maintain  equilibrium.     Lets  look  at  some  other  examples.    Smiling  has  been  found  to  be  contagious.    Is  this  a  positive   or  negative  feedback  loop?    Does  one  smile  increase  or  decrease  the  chances  of  another?    

How  about  another  important  teen  issue?   Sleep  and  fatigue  can  be  modeled  in  a     feedback  loop.    Is  this  a  positive  or   negative  loop?    Does  disrupted  sleep     (like  sleeping  next  to  your  phone)     increase  or  decrease  the  likelihood     of  a  poor  nights  sleep  the  next  night?  

Your Assignment:

Submit your feedback loop diagrams. The easiest way to do this is to create them in Google Drive using the "drawing" app when you click on the "NEW" button. If you go to "more" you should see an option that is "Google Drawing". To submit, just share "anyone with the link" like you would any other Google Doc and as explained in the Google Doc tutorial in the intro module to the course.