physical science exam 1

population growth

the increase in the number of individuals in a population

current population

8 billon

1800s population

1 billion

1900s population

1.65 billion

2000s population

6.12 billion

what percent of the world population lives in less developed areas

80%

Population of developed countries

stable or decreasing

in a few centuries what will the population be

10 billion

population growth results in

urbanization

what percentage of population live in urbanized areas

50%

Urbanization

An increase in the percentage and in the number of people living in urban settlements. has resulted in people living in areas more prone to natural disasters

At 11,900 feet above sea level, what is the highest capital city in the world?

La Paz

the city in the mountains. has increased threat of natural disasters including mudslides and earthquakes

the increase in population has also increased

the demand for water and energy resources

water distribution

97.2% salt water, 2.8% fresh water

What percent of water is in icecaps and glaciers?

2.15%

what percentage of water do people have access to?

0.65% found in lakes, streams & groundwater

Energy

the capacity to do work

before 1850 what was the main energy source

wood

fossil fuels

Coal, oil, natural gas, and other fuels that are ancient remains of plants and animals.

fossil fuels make up what % of total energy source now

80%

Alternatives to fossil fuels

Sources of energy that don't require any use of hydrocarbons and it's compounds.

Solar, wind, geothermal, biomass, water, uranium, and hydrogen

nuclear energy

The potential energy stored in the nucleus of an atom. It is highly radio active which is extremely dangerous

hydroelectic power

its the process by which water turning a wheel signals a generator to produce your electricity; kentic energy.

destroys with biodiversity and the environment because it requires damn

2019 energy breakdown

Petroleum - 37%

National gas - 32%

coal -11%

nuclear -8%

renewable -11%

climate change

a change in global or regional climate patterns, in particular a change apparent from the mid to late 20th century onwards and attributed largely to the increased levels of atmospheric carbon dioxide produced by the use of fossil fuels.

global warming

An increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes)

Effects of global warming

intensified storms, ocean acidification, new weather patterns, melting ice sheets& glaciers, rise in sea level, loss of biodiversity

Largest contributor to global warming

burning fossil fuels (oil, petroleum, gas, coal) adds CO2 to atmosphere

why are they called fossil fuels?

They come from decomposition of organic material from 100-500 million years ago.

creation of fossil fuels

Over millions of years in the right conditions dead animals and plants can become fossil fuels.

peat

Extensive deposits of undecayed organic material. first set in the creating F.F

Lignite

A soft, brownish-black coal. second step in making f.f

peat under segment with extreme pressure

sub-bituminous

softer and more crumbly than bituminous coal. third step in F.F needs heat & time

Bituminous

the second-most energy-rich type of coal. fourth step in F.F

anthracite

the cleanest-burning coal; almost pure carbon.coal of a hard variety that contains relatively pure carbon and burns with little flame and smoke. last step in FF

steps to F.F

peat

lignite

sub-bituminous

bituminous

anthracite

(must be segregated from oxygen, so that the carbon cannot escape)

in natural circumstances, carbon is slowly released and absorbed this is the balanced process BUT

because people are releasing CO2 in extreme amounts which accumulates in the atmosphere

Greenhosue effect

the trapping of the sun's warmth in a planet's lower atmosphere due to the greater transparency of the atmosphere to visible radiation from the sun than to infrared radiation emitted from the planet's surface.

the greenhouse effect is

a natural phenomenon that maintains Earth's temperature range

greenhouse gases

Gases such as carbon dioxide, methane, nitrous oxide, water vapor, and ozone in the atmosphere which are involved in the greenhouse effect.

Age of Earth

4.5 billion years old

endal thinks solar luminosity 4.5 billion was

70%-75%, 30% less than today. this means that the east should be cold enough to freeze over right now but it didn't because of greenhouse gas

Endal solar luminosity formula

Formula:L = R2 T4 where: L = luminosity given in terms of the Sun's luminosity. R = radius given in terms of the Sun's radius T = temperature given in terms of the Sun's temperature.

Why is CO2 important?

it is a critical component of earths biosphere. Earths average temperature would be around 0 degrees Fahrenheit without it. the most abundant GHG. Disolves into the ocean. reacts with h20 to create carbonic acid

carbonic acid

a very weak acid formed in solution when carbon dioxide dissolves in water. lowers ph in the ocean

What are the impacts of a lower ph in ocean water?

Ocean acidification, marine ecosystem can't be damaged and shelled creatures can't make strong shells

Mauna Loa Observatory

The place where atmospheric carbon has been measured since 1958. The undisturbed air, remote location and limited influence of vegetation and humans make it ideal.

ppm

parts per million

what is the current atmospheric CO2 level in ppm

419.07 ppm as of 01/17/23

CO2 levels have not

been this high in the last 800,000 years

what is the overall them increase during the 20th century

~0.3∘C (1.3∘F)

proxy data

preserved physical characteristics of the environment that can stand in for direct measurements

paleoclimatology

study of past climates

examples of proxy data

tree rings, ice cores, fossil pollen, ocean sediments, corals

How de we reconstruct temperatures in the geological past?

use natural processes that are temperature dependent like isotopic fractionation

isotopic fractionation

partitioning of isotopes between two substances with different isotopic ratios, preferentially incorperate lighter isotope

oxygen-16

Protons- 8

Neutrons- 8

oxygen-18

Protons- 8

Neutrons- 10

Oxygen 16 and 18 have

different atomic Masses, with 16 being ligther

lighter isotopes-

take less energy to move

heavier isotopes -

take more energy to move

Isotopic fractionation

partitioning of isotopes between two substances with different isotopic ratios, preferentially incorperate lighter isotope

The 16O evaporates \________ than 18O

easier

describe the process of isotopic fractionation in oceans with oxygen in cold temps.

Since 16O evaporates more easily than 18O, more 18O becomes concentrated in the ocean, as 18O is preferentially removed by precipitation. The glaciers will grow, and more and more 16O gets locked up in glaciers as the cold climate continues. The 18O/16O ratio in the seawater increase

describe the process of isotopic fractionation in oceans with oxygen in warm temps.

16O still evaporates easier, and 18O is preferentially removed by precipitation but because there are no glaciers, the 16O will flow back to the ocean and so more 16O is in the water. so the 18O/16O ratio in the seawater decreases

the ratio between 18O and 16O in the ocean acts as a

Thermometer

Foraminifera

shell builders - CaCO3

One of a group of tiny single-celled organisms that live in surface waters and whose secretions and calcite shells account for most of the ocean's carbonate sediments.

ice cores

bubbles of ancient air including H2O, used to see the ratio between 16O and 18O

PETM

A time period known as the Paleocene-Eocene Thermal Maximum; 56 million years ago; the climate warmed by 5°C in 20,000 years. The PETM has been considered the best ancient analogue for the current climate change because 2/2/2321What is "PETM"?Paleocene-Eocene Thermal Maximum (55 Ma)•

thermohaline circulation

an oceanic circulation pattern that drives the mixing of surface water and deep water. driven by the denisty and differences. channels oxygen, heat, carbon and nutrients around the globe

system

An entity composed of diverse but inter-related parts that function as a complex whole

systems are made up of what

components or sub-systems

subsystems are

interrelated and interacting. they cat together to maintain a healthy state of body - self regulating

what are the four components of the earth

atmosphere, hydrosphere, biosphere, lithosphere

State

is the set of important attributes that characterize a system at a particular time ex.) body temp or blood pressure

Couplings

links between system components. allow for regulation of a system

coupling example

cold person, electric blanket

positive coupling

a change in one component is a stimulus that leads to a change of the same direction in the linked component (arrow)

positive coupling example

Blanket temperature and Body TemperatureChange in SAME Direction (blanket gets hot and so do you)

negative coupling

a change in one component stimulates a change of the opposite direction in the linked component ( dot)

negative coupling example

Blanket temperature and Body TemperatureChange in OPPOSITE Direction you are too hot, turn down blanket.

Combination of a positive and negative coupling creates a

Negative Feedback Loop (+ times - is negative)

negative feedback loop

A feedback loop that causes a system to change in the opposite direction from which it is moving. minimizes disturbance and leads to stability.

positive feedback loop

Causes a system to change further in the same direction. amplifies disturbances. like about the two blanket and mismatched remotes

Albedo Effect

the ability of a surface to reflect away solar radiation

Light colored surfaces

reflects more heat and light (ice and clouds)

dark colored surfaces

Absorb more light rays which are transformed into heat (ocean and land)

albedo values

0: no reflection

1: complete reflection of light

avg albedo of earth \~ 0.31 (31%)

snow=80-90%

clouds=50-55%

bare sand= 30-60

grass=15-25%

city=10-15%

forest=5%

Albedo is a measure of

reflectivity of a surface

Water in the oceans or on a lake is

one of the darkest surfaces -reflecting less than 10% of the incident ligh

Clouds and snow or ice are among

the brightest surfaces -reflecting 70%-90% of the incident light

Examples of couplings and feedbacks in the Earth System (positive)

albedo effect: atmospheric temp rises, ice melts, less light surfaces, (+)*(+)*(+)=+

Examples of couplings and feedbacks in the Earth System (negative)

effects of clouds: temp in atmosphere, rises, more evaporates, more clouds, ore solar redaction absorbed (+)*(+)*(-)\*(+)=-

it is \___ to predict the effects of \_____ on the earth system and climate

difficult; anthropogenic CO2

anthropogenic

derived from human activities

Drake Passage

separates South America from Antarctica. allowed for ACC

Antarctic Circumpolar Current

The current driven by powerful westerly winds north of Antarctica. The largest of all ocean currents, it continues permanently eastward without changing direction.ACC

Initiates ICE-ALBEDO feedback and Antarctica keeps getting colder and colde

opening of the drake passage

Lithosphere - Antarctic, South American Plates move apart

Hydrosphere - Circum-Polar current initiated

Energy System - Heat can't get to Antarctica

Atmosphere - Also isolated from heat, gets very COLD

Hydrosphere- Glacier Ice begins forming in Antarctica

what is science

A way of asking and answering questions about the physical universe - a process of inquiry

Scientific Method

A series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions.