REM 100

global change

global change

human induced transformation of the global enviornment

enviornment

external conditions that an organism lives in like social, economic, physical.

examples of global issues

climate change, energy crisis, world hunger, pollution, population explosion

global issues charecteristics

global or large-scale effects, persistent, worldwide attention, many moving parts, inter-related to other global issues, no simple solution, interdisciplinary knowledge, interdependence between countries, solutions have trade-offs, challenge status quo

institution

structures required for functioning society

system

interdependent parts enclosed in a defined boundary

earth sytems

biosphere, hydrosphere, lithosphere, atmosphere

stratosphere

ozone layer

troposphere

weather

atmosphere

controlling global energy balance and climate change

hydrosphere

fresh water avalibility

cryosphere

sea levels rise

lithosphere

source of all raw materials

pedosphere

platform for food production

biosphere

photosynthesis and the carbon cycle

anthroposphere

environment that is made or modified by humans

earth is a

complex system and closed system as a whole

closed system

energy exchanged with outside, matter stays inside

open system

energy and matter exchanged with outside

biogeochemical cycle

pathway that describes how substance moves through spheres of earth system

flux

flows the substance

energy

drives the cycle

reservoirs

holds substance

perturbations

disturbance in the flow of substance, can be natural or human caused

equilibrium

steady state or cyclical

perturbation example

landslide, pollution, CO2 concentration

response

system’s reaction to distrubances

types of system responses

linear, feedback, non-linear (exponential, episodic, catostrophic)

linear response

response is proportionate to disturbance

feedback loop

response to perturbation effects magnitude of perturbation

positive feedback loop

increased magnitude, exponential

negative feedback loop

decreased magnitude, episodic

spatial scale

extent to which something occurs

spheres interact via cycles

composed of reservoirs, fluxes and energy

system thresholds

are tipping points that can lead to sudden changes

planetary boundaries

9 boundaries humans must respect

weather

current state of atmosphere

climate

statistical description of weather over long period of time(typically over 30 years)

Robert Heinlein’s quote

climate is what you expect, weather is what you get

climate change

significant and lasting change in statistical distribution of weather

climate change has been detected through

global surface temps, precipitation, extreme weather events, cryospheric changes, sea level

without atmoshphere

all radiation would be reflected or emitted back

with atmosphere

some radiation is absorbed

atmospheric gases

also emit radiation, thermal and evaporation make up the difference

forcing the climate system

change amount of energy from sun, change concentration of greenhouse gases and aerosols, change surface properties

land use change

darker and drier surface absorbs more energy and turns it into heat

mechanisms of climate chnage

natural greenhouse effect, force climate system, concentration and rate of change of CO2 is unprecedented

greenhouse gas

trap heat in the atmosphere and warm the planet

greenhouse gas effect

heat trapped near earth due to greenhouse gases

A-O general circulation models

show observed changes in earth are human caused

water cycle is a

closed system

avg concentration of CO2

417ppm

greenhouse effect other than CO2 with large effect

CH4 methane

natural resource

source or supply that occurs in nature without human action

material resources

of use to individuals and society

flows of energy

can be harnessed for useful purposes (solar, hydro)

attributes of the enviornment

contribute something of value like pollination (ecosystem services)

classification of natural resources

basis or origin, stage of development, renewability

biotic

living and organic

abiotic

non-living and non-organic

actual

surveyed and currently exploited

reserve

surveyed and can be exploited in future

non-renewable

form slowly or non-naturally (fossil fuels, metals, minerals)

renewable

form equally fast or faster than they are used (soil, water, land)

exhaustive vs inexhaustible

finite vs will not run out soon

factors that can change available time of resources

new reserves, new technology, change in economic conditions

resource cycle

extraction/harvest, concentration/purification, production of goods, consumption of goods, end of usefulness, reuse/recycling, waste disposal, waste assimilation into environment

factors that can change recycle practices

scarcity of original resource, technology, reusing is cheaper

reuse/recycling types

produce primary resource, produce secondary resource

sink

part of the environment used for disposal of valueless material

waste

something the owner no longer wants

recycle

converts material that lost their value into new materials

most natural resources are

exhaustable

objective of environmental resource management

manage interaction and impact of humans on the enviornment

annual extraction of materials since 1970

gone up from 22 to 70 billion tons, trade is the main reason why

global material use has gone up

due to consumption

material productivity

economic activity per unit of natural resources extracted(kg)

material intensity

natural resources extracted (kg) per unit of economic activity

how does material intensity lower in a better economy but the world is higher in material intensity

switch from material efficient economies like japan and europe to less material efficient ones like India and china

impact =

population x affluence x technology

affluence

average consumption per person (gdp per capita)

technology

how resource intensive production of affluence is

IPAT framework

the main drivers of human impact on enviornment

time it takes for a population to double

70/population

the great transformation

transformation of ecosphere from it natural state by human action

sustainable development

meets the needs of the present without compromising ability of future generations

hunter gatherer society

altered environment, depleted it and moved on

agrarian society

domesticated plants and animals, increased efficiency, larger populations

industrial revolution

steam engines fueled by coal, factories and transportation systems

anthropocene

human activities became major geological force

growth rate =

birth rate - death rate + migration

demographic transition model

transition from high birth and detah rates to low birth and death rates through industrialiation

global population growth is

decreasing and 11b predicted for 2100

high stationary

pre industrial, death and birth rates are high

early expanding

decline in death rate

late expanding

decline in birth rate

low stationary

both birth and death rates are low

declining

birth rate below death rate

canada dtm

stage 4, low stationary

CLEAN fresh water

is exhaustible