Lecture 7

Question 1

positive feedback loop

Answer 1

amplify change
ex. global warming > climate change > ice melts > less ice reduces ability to reflect sun’s heat > more global warming

Question 2

negative feedback

Answer 2

regulate an imbalance
CO2 in atmosphere > more plants grow > plants consume CO2 through photosynthesis > CO2 concentration reduces

Question 3

carbon footprint

Answer 3

combination of all greenhouse gas emissions by an entity or individual
measured in CO2 equivalence

Question 4

carbon neutrality

Answer 4

achieving a net zero carbon emissions from a process by offsetting or sequestering an equivalent amount (or buying carbon credits)

Question 5

how can engineers tackle climate change

Answer 5

innovative ways to reduce energy/material consumption
increase system efficiency
develop renewable energy sources (hydrogen and bioenergy)
life cycle assessment

Question 6

life cycle assessment

Answer 6

evaluation of the environmental impacts associated with all stages in a life styles

stages:
extraction of raw materials, processing, distribution, use, recycling, and disposal

used to select most sustainable

Question 7

life cycle cost

Answer 7

analysis of cost from initiation to disposal

costs:
initial capital cost, operating/maintenance, renovation/replacement, and disposal/decommissioning