ENV100 Lecture Notes Mar 23, 2012
Remote Sensing, GIS and Turtles
Guest lecture: Amy Mui
What is GIS?
Geographical Information System
o CARTOGRAPHY(map making)+ DATABASE(Technology)+ STATISTICS(spatial)
What can it do?
Allows you to visualize, question and interpret data on a large spatial scale
Reveals spatial patterns and relationships
Help you to answer questions and solve problems
Who uses it?
Lot’s of People!
Government, Natural Resource Managers, Conservation Organizations, Universities,
Businesses,..... and maybe you!
What is remote sensing?
The acquisition of information on an object/area by use of a sensing device that is not in
contact with the object /area under investigation
Continual habitat loss
High nest predation and juvenile mortality
High female road mortality
o = Population CRASH
STEP 1: Find a turtle and follow it around
STEP 2: Measure the habitat that it uses
STEP 3: Map this habitat on a large scale
The road to extinction-snapping turtle
The snapping turtle is a species at risk
Suffered from decades of habitat loss and fragmentation
o We do not know how many turtles are left
Long-lived species, late to mature, cannot sustain significant adult mortality
The MNR permits hunting of Snapping Turtdles
o Two per day
o There is no way to regulate or even monitor how many turtles are being taken
from the wild
Measuring CFCs and their replacements from space
Guest Lecture: Felicia Kolonjari
• CFCs, HCFCs, and stratospheric ozone
• The Atmospheric Chemistry Experiment
CFCs, HCFCs, and HFCs – why do they matter?
o Man-made organic compounds containing carbon, chlorine and fluorine.
o Used as refrigerants, propellants and solvents.
o It was thought these compounds were not harmful due to their low reactivity
under lower atmosphere conditions.
o In 1974, Molina and Rowland showed that it was this property which allowed
CFCs to diffuse to the stratosphere.
o The dominant reaction of CFCs (occurring in the stratosphere) is a photo-induced
scission of the C-Cl bond
Hydrochlorofluorocarbons (HCFCs) and Hydrofluorocarbons (HFCs)
o HCFCs have a lower ozone depletion potential than CFCs
o HFCs have negligible ozone depletion potential due to their lack of chlorine
o HCFCs have lower global warming potentials than CFCs (CFC-11: 4750 vs. HCFC-
o Most HFCs have lower global warming potentials than CFCs (an exception is HFC-
o Sources: anthropogenic emissions; replacements for refrigeration/air
conditioning and blowing agents
o Sinks: removed from the atmosphere by reaction with the OH radical in the
troposphere prior to transport to the stratosphere
An FTS in space...The Atmospheric Chemistry Experiment
The Atmospheric Chemistry Experiment
o On-board Canadian satellite SCISAT launched on August 12th 2003
o The primary goal of the mission is to study the chemical and dynamical processes
controlling ozone distribution.
o The primary instrument is a Fourier transform spectrometer (ACE-FTS)
High spectral resolution (0.02 cm-1) infrared FTS
Wide spectral range provides profiles of over 30 atmospheric species
(including 3 CFCs, 3 HCFCs and 2 HFCs)
Annually Repeating Measurement Latitudes
High inclination (74°), circular, low Earth orbit (650 km).
This orbit allows sampling of the polar, midlatitude and tropical regions.