earth science ch.13-19

difference in % distribution of land and water in the northern and southern hemispheres

The northern hemisphere is about 67% land and 33% water, while the southern hemisphere is 80% water and 20% land

Bathymetry

the measurment and study of the ocean floor, debth and shape

3 major features of passive continental margins

1. continental shelf— gently sloping, submerged extension of the continent

2. continental slope— steep area where the seafloor descends from the shelf to the abyssal ocean basin

3. continental rise— gently sloping area made up of thickened sediments that settle at the base of the slope

passive and active continental margins differences

passive is calm, stable, quiet, and doesn’t occur near plate margins

active is shaky and volcanic

3 types of seafloor sediement/description

1. terrigenous- made of weathered rock/land originating mineral grains carried to the ocean by rivers, wind, glaciers (continental sand, clay grains)

2. biogenous- made of shells/skeletons of sea organisms (siliceous ooze)

3. hydrogenous- formed directly from precipitating minerals from seawater

2 most abundant elements dissolved in water

chlorine and sodium = sodium chloride (NaCl)

factors affecting seawater density 

temperature, salinity, pressure

plankton, nekton and benthos description

plankton- drifters, usually microscopic and cannot swim against current (copepods)

nekton- free-swimming organisms that are not reliant of currents (fish) 

benthos- animals living on the bottom/seafloor (crabs)

explain efficiency of energy transfer between trophic levels

Energy goes to producers, then to primary consumers, then to secondary, and then to tertiary consumers. Most of the energy is wasted; only about 10% is used. 

Ocean currents influence on climate/examples

the climate regulation, moving heat/moisture around

ex. gulf stream, california current, the peru

3 factors that affect the height, length and period of a wave

wind speed, duration, and fetch (distance the wind blows over the waters surface)

motion of a floating object as a wave passes

rises up and down with a wave crest and troughs, does not go forward mostly returns to orginal position

ways that waves cause erosion

hydraulic action- pressure from crashing waves compacting air/water into coastal rocks

abrasion (corrasion)- sand, pebbles and other debris scraping the coastline (sea cliffs)

hard stabilization examples (man-made structures to protect the shore from erosion/manage sand transport) 

groins, jetties, and seawalls

spring and heap tide differences/explanation

spring- occur twice a month with the new/full moon when the sun, moon, and earth align, making higher/lower tides

heap- twice a month during the first/quarter moons. creating smaller tidal range (smaller high/low tide)

weather vs. climate description 

weather- short term conditions of the atmosphere at a particular point in time (temp, humidity) 

climate- average behavior of weather over an extended period of time and region (30 yrs)

elements of weather and climate

temperature, humidity, amount/type of precipitation, air pressure, wind (velocity and direction), cloud cover 

ozone molecule description/importance to life of earth

O3, oxygen in stratosphere. absorbs dangerous UV radiation from the sun, protecting from DNA damage

In order from the earth the 4 layers of the atmosphere/describe

1. troposphere- closest to earth, temp decreases with altitude. The majority of mass, all weather occurs here

2. stratosphere- temp increases with altitude b/c the UV rays

3. mesosphere- temp decreases, meteors burn up here

4. thermosphere- temp increases rapidly, very tenuous air, aurorae occur here

what is the cause of seasons

the earth tilting 23.5 degrees, and orbiting around the sun at different parts causing some sections to experience more or less light 

relative humidity

temp. dependant, does not indicate real water vaper

how do clouds form

water vapor in air cooling and condensing into tiny water drops or ice crystals 

3 characteristics of cirrus, stratus, cumulus clouds

cirrus- thin, high clouds, made of ice crystals

stratus- low, gray blanket, may drizzle

cumulus- puffy, cottony, fair weather clouds 

rain, drizzle, and mist size 

rain- >0.5mm, falls quickly 

drizzle- <0.5mm, falls slowly 

mist, extremely fine, floating in the air, reduces visibility 

how does hail form 

intense thunderstorms updrafts, goes up and down collecting ice layers until they fall 

air pressure definition

pressure exerted by weight of air pushing down over a surface, its atmosphere pushing down all directions due to gravity

3 factors that combine to form wind

1. pressure, gradient force (air moving high/low)

2. coriolis effect- deflecting wind because of rotation 

3. friction- decrease, deflects wind near the earth surface 

The Coriolis effect influencing air movement

deflecting moving air, right= Northern hem, left= Southern hem

2 basic wind measurements

direction - wind vane

speed- anemometer

el nino vs la nina

El Niño- warmer sea surface temp in centeral/eastern equatorial Pacific causes trade winds to weaken 

La nina- colder air temp causing stronger winds in same region 

definiton of air mass

large body of air with consistant temp and moisture consistent

compare cold fronts and warm fronts

cold- forces warm air up rapidly, causing heavy rain, storms, and rapid temp drops 

warm- air rising slowly over cold air causing steady rain and warmth

stages of how a thunderstorm forms

cumulus stage- air rises forming cumulus clouds

mature stage- strong winds, heavy rain, lighting 

dissipating stage- downdrafts dominate, rain stops, clouds dissipate 

how do tornadoes form and when

warm, moist air at the surface meets cold dry air, strong winds are most common in spring (april-june)

compare hurricane eye and eye wall

hurricane eye- calm, clear center, light winds

eye wall- encompasses the eye, greatest winds and most intense rain 

kinds of damage occure from a hurricane

storm surge (flooding caused by ocean water), wind damage, inland flooding (excessive rain)

describe why CO2 levels have risen and the consequences of it

CO2 levels have been rising due to burning fossil fuels, deforistation,  and industrial/transport emissions. consequences are global warming, melting ice caps, stronger weather patterns/events, ocean acidification 

what other types of problems have arisen from aerosols and sea level rise 

aerosol issues = air pollution, acid rain, climate effects, sea level rising because coastal flooding, loss of habitats, and salt water intrusion