Global Catastrophe at the Movies (L29)

Question 1

What is a modern example of a threat of impact and what happened?

Answer 1

The Impact of Tunguska in Russia

a mysterious explosion occured
vibrations were recorded as far as 1000 km away
people in closer range were blown into the air and some died
based on observations later, it was determined that it was caused by a large meteorite about 50m in diamter

Question 2

What was the comet in Deep Impact influenced by?

Answer 2

Observations made on a comet that was seen to be headed to Jupiter

Question 3

What is the Shoemaker Levy 9?

Answer 3

A comet that crashed into Jupiter in 1994 in 20 large pieces leading Jupiter to have Earth-sized scars that took months to dissipate in its upper atmosphere

Question 4

What are the odds of a sizable object hitting the earth?

Answer 4

the frequency of a very large impact is much lower than the frequency of small impacts

Question 5

What was the NASA spacecraft “Deep Impact” being launched into space for and what was found?

Answer 5

It was to strike the comet with a 370kg mass

the impact wasn’t strong enough to change the comet’s course but it provided indications of the composition/physical properties of the comet whcih contained more dust and less water than expected

Question 6

What else was found out about the comet’s surface?

Answer 6

that it was more porous and rubblier than expected

Question 7

How is the Earth’s magnetic field generated? and what movie covers this?

Answer 7

its generated by the convective flow of outer core material, with hot material rising and cooler, dense material sinking. this creates an electric current that, in turn creates a magnetic field

the Core

Question 8

The Earth’s magnetic field fluctuates in ____ and ______

Answer 8

intensity and polarity

Question 9

What is an easier route to get to the core than the method used in the movie “The Core”?

Answer 9

down a mid-ocean ridge (at a divergent boundary) where the lithosphere is thinnest and in a state of tension. a lot easier to drill

Question 10

What is the basic idea of how the circulation system in the ocean work?

Answer 10

warm, less salty, low-density seawater flows at surface toward poles

cold, more salty, high-density water flows along seafloor toward equator

Question 11

What does Global Warming do?

Answer 11

it serves to decrease temperature differences between the poles and the tropics, making thermohaline circulation much weaker

Question 12

What would be a result of Global warming shutting off the thermohaline conveyor system?

Answer 12

the result is that areas that would normally be warmed by the warm surface current would become colder, while the tropics would become hotter

Question 13

What is a difference in the efffect of global warming between reality and “Day After Tomorrow”?

Answer 13

these changes would take place over at least several decades not a few days like the movie

Question 14

What is a reason that can compound the problems of the Earth’s system?

Answer 14

the Earth system is linked to everything else

Question 15

What is at the root of the worsening of the problems of global warming?

Answer 15

Humans

Question 16

How do humans worsen global warming?

Answer 16

The human population increases so more people means more energy consumption (primarily from the burning of fossil fuels)

At the same time, the use of energy from fossil fuels is increasing per person, so as the population increases, co2 emissions are increasing, which means global warming

Question 17

How does the beef industry add to global warming?

Answer 17

cows are producers of greenhouse gas, so adds to volume of greenhouse gases produced

to produce more beef, we need more room so we cut down forests and replace it with open lands

so ultimately, increasing in methane emissions form cattle, and FURTHER increase co2 concentrations by chopping down trees

Question 18

What else leads to global warming other than co2 emissions?

Answer 18

oceans and landmasses are warming