Oceans & Water Distribution
Where is most of Earth's water found?
Oceans.
What process turns liquid water into water vapor and moves it into the atmosphere?
Evaporation.
What property makes ocean water denser than freshwater?
Salinity.
Name the lowest layer of Earth’s atmosphere where weather happens.
Troposphere.
What phase of the moon occurs when the side facing Earth is fully lit?
Full moon
Name three locations where freshwater is stored on Earth’s surface or subsurface.
Rivers, lakes, swamps, glaciers/ice, groundwater, aquifers (any three correct).
What is transpiration?
Transpiration is the release of water vapor from plants into the atmosphere.
What causes tides on Earth?
Tides are caused mainly by the gravitational pull of the moon and the sun on Earth's oceans (moon has the stronger effect).
What gas is a major greenhouse gas and helps trap heat in the atmosphere?
Carbon dioxide (CO2) or methane (CH4) — both are greenhouse gases.
What alignment causes a solar eclipse?
Solar eclipse occurs when the Moon is directly between the Sun and Earth, blocking sunlight from reaching part of Earth.
Which graph type is best for showing the relative proportions of water stored in oceans, glaciers/ice, groundwater, lakes, rivers, and the atmosphere?
Circle/pie graph.
List the main steps required in the water cycle (give at least four).
evaporation, condensation, precipitation, infiltration, runoff, transpiration, groundwater flow.
What are two major factors that create ocean currents?
Major factors creating ocean currents: wind (surface currents), differences in water density due to temperature and salinity (thermohaline circulation), plus Coriolis effect and
Explain what a front is in weather terms.
A front is the boundary where two air masses of different temperature and humidity meet; fronts often cause changes in weather.
How does the tilt of Earth affect the seasons?
Earth's tilt causes seasonal changes because tilt changes the angle and duration of sunlight a hemisphere receives during the year.
Approximately what fraction (or percent) of Earth's total water is freshwater available in rivers and lakes (order of magnitude: very small, small, moderate)
Very small: only a tiny fraction (surface freshwater in rivers and lakes is less than 1% of total Earth water — often cited ~0.3% of freshwater in rivers/lakes relative to total water).
How does the sun’s energy drive evaporation and influence atmospheric conditions that lead to the water cycle?
The sun provides energy that warms water, causing evaporation; warm moist air rises and cools, leading to condensation and precipitation — driving the water cycle.
: If ocean surface temperature increases, predict one likely effect on surface water density and one effect on local weather/hurricane potential.
If surface temperature increases: surface water may become slightly less dense (thermal expansion), but increased heat raises evaporation and storm energy — likely increasing hurricane potential and heavier rainfall.
How does uneven heating of land and water contribute to local wind systems?
Unequal heating: land heats and cools faster than water, creating pressure differences; air moves from high to low pressure producing local winds (sea breezes by day, land breezes by night).
Briefly describe a model using a lamp (sun), a globe (Earth), and a smaller ball (moon) to show how lunar phases change.
se a lamp as the Sun, a tilted globe as Earth, and a smaller ball as the Moon. Keep the lamp fixed; rotate and orbit the small ball around the globe to show how the lit portion visible from Earth changes (phases).
Explain why groundwater is an important freshwater resource and one reason why its distribution and quality vary around the world.
Groundwater supplies drinking water and irrigation for many communities; its distribution and quality vary because of differences in geology (porosity/permeability of aquifers), recharge rates, overuse (overdraft), and contamination from surface pollutants.
Name one simple classroom investigation that would show how temperature affects the rate of evaporation (briefly describe one independent and one dependent variable).
Place identical open containers of water at two temperatures (warm vs. cool). Independent variable = temperature; dependent variable = mass or volume of water lost over time (evaporation rate). Expectation: warmer container shows faster evaporation.
Describe an investigation to measure how salinity affects water density
Prepare several water samples with increasing salt concentrations; measure density with a hydrometer or observe floating of objects; expected trend: higher salinity → higher density.
Given increased moisture evaporating from warm oceans, explain one effect this has on hurricane formation and one effect on regional rainfall.
With increased moisture from warm oceans: hurricanes can gain strength (more energy and moisture), leading to more intense storms and increased regional rainfall.
Compare two planets (one with a thick atmosphere and one with almost no atmosphere) and explain how atmosphere affects surface temperature and ability to support life.
Planet with thick atmosphere (Venus-like) traps heat → very high surface temps and strong greenhouse effect (poor for life). Planet with almost no atmosphere (Mercury-like) has huge temperature swings and little protection — also poor for life. Atmosphere moderates temperature and can support life by providing pressure, gases, and climate regulation.