Agenda: February 21st, 2013 Warm-up: Describe how invasive species

can be harmful to a native ecosystem. Give an example

Cornell Notes (pg. 27)◦How to Clean Up Oil Spills

Introduce Oil Spill Lab◦Work on pre-lab questions

Homework: Finish pre-lab questions (3 questions)

How to Clean Up Oil Spills

Oil tankers are the largest ships to sail in the ocean

Usually, these ships are safe

An oil rig exploded in the Gulf of Mexico

An estimated 210 million gallons of oil leaked into the Gulf over a 3 month period

Except on April 20th, 2010

Deepwater Horizon Oil SpillThe spill as seen from space on May 24th, 2010

When these spills happen, oil spreads out over the surface of the water in a large SLICK

These oil slicks can cause huge environmental damagesHowever, there are numerous ways to contain them, and clean them up

Basically a large float that surrounds the slick

As the boom is pulled into a boat, they can skim the oil off the top

The oil slick shrinks until it is completely cleaned up

Method 1: Containment boom

Vacuuming oil off the surface of the water

When detergent is sprayed on oil slicks, the oil breaks up into clumps which sink to the bottom of the ocean

Method 2: Spray detergent on the spill

These bacteria eat oil slick as food

As they reproduce, they eat more and more oil

When slick is gone, their food source is used up and the bacteria die

Method 3: Oil-eating bacteria

If a slick is small, it can sometimes be absorbed by special absorbent pads

Then, these pads can be removed from the surface of the water

Method 4: Absorbing oil