Weather and Climate
Atmosphere- the invisible ocean of air we live in. It is made up of 78% Nitrogen, 20.9% Oxygen, and .9% Argon. Small amounts of other gases are also present such as carbon dioxide and water vapor.
Molecules- are the gases that make up our atmosphere. As gas molecules move about, they spread outward and upward. There are more molecules near the Earth’s surface because of gravity. The higher up you go in the atmosphere the less dense the molecules are meaning the atmosphere thins out as you go higher.
Atmospheric pressure- is produced y molecules hitting a surface.
Altitude- height
Barometer-measures atmospheric pressure. Most barometers are made of mercury. When the mercury drops significantly this means a storm is approaching. The mercury will rise again once the storm has passed.
There are four layers of the Earth:
- Troposphere- also called the zone of weather, because it’s the lowest layer where all the weather occurs. Temperatures decrease with increasing altitude (meaning the higher you go up, the colder it is.)
- Stratosphere- is the 2nd layer of the atmosphere. The temperatures increase with increasing altitude. This layer contains the ozone layer. The ozone filters harmful ultraviolet radiation from the sun.
- Mesosphere- is the 3rd layer of the atmosphere. Temperatures decrease with increasing altitude.
- Thermosphere-surrounds the mesosphere and temperatures increase as you go up in altitude. This layer is also sometimes known as the ionosphere.
Wind- is the movement of air.
Cold air- moves downward. It is heavier.
Warm air- rises because it is lighter.
Convection- is when cooler, denser air moves from an area of high pressure to low pressure (the forests to the streets), it pushes the warm, less dense air upward. This process of warmer air being pushed up is called convection.
The water cycle- is a continuous process of water moving from air to ground. The four stages are:
- Precipitation- water that falls to the surface of the Earth (snow, ice, hail or rain)
Much of the precipitation goes into the ground and is called groundwater. If it does not go into the ground it is called runoff or surface water.
- Evaporation –water molecules that escape and become water vapor
- Transpiration- groundwater is absorbed by the roots and plants and the unneeded water is evaporated from tiny openings called the stomata in the leaves in a process known as transpiration.
- Condensation-example- the dew on a leaf, the bathroom shower that has fogged up.
Humidity- is the amount of water vapor in the air.
Facts:
- Warm air can hold more water vapor than cool air.
- Warm air can hold up to five times as much water vapor as cold air on a winter day. This is why there is more humidity in the summer.
- 100% humidity means that the air is saturated with the maximum amount of water vapor that it can hold at a certain temperature. This could mean that is it raining. 50% humidity means that the air is holding half of the water vapor that it can at that temperature.
Relative humidity- tells how much water vapor is in the air compared to the total that could be in the air at a given temperature.
Dew- is the water droplets that form on the grass and other surfaces. If it is below freezing the dew becomes frost which is harmful to plants.
Clouds must have three things in order to form. 1. water vapor in the air 2. cooling in the atmosphere 3. condensation
There are 3 basic shapes of clouds:
- Cumulus-piled up
- Stratus-spread out
- Cirrus-hair-like strands
Cumulus clouds from when moist air collects rapidly over a small area. The moisture will pile up and form cumulus clouds.
Cumulonimbus clouds- creates thunderstorms.
Stratus clouds- form as air rises gently over a large area and then cools slowly. They are not piled up, but spread out over the sky.
Cirrus clouds- are the highest in the atmosphere. They look like wispy feathers.
Large areas of air with the same temperature and moisture levels of the surface are referred to as airmasses.
Air masses are very large, and move like giant air bubbles over the earth.
Cold air masses produce cooler weather, and warm air masses bring warmer weather.
Air masses are classified by their temperature and moisture, and get their names from the source regions where they develop.
Temperature characteristics are defined by:Arctic, Antarctic Polar, Equatorial, and Tropical.
Maritime- an air mass that is moist, and forms over the oceans
Continental- an air mass that is dry, forming over the continents
Wet air masses-form over oceans
Dry air masses-form over continents
Equatorial air masses- considered wet, they form over areas with rainforests which adds moisture
Arctic and Antarctic air masses-considered dry, there is little evaporation and very low temperatures.
The temperature of a place depends on the source of the air mass and the path of the air mass.
The leading edge of a moving air mass is called a front.
A cold front occurs at the edge of a cold air mass.
A warm front occurs at the edge of a warm air mass.
If air masses are not moving, then the space between the masses is called a stationary front. Stationary fronts bring overcast, rainy weather.
Occluded fronts occur when two cold air masses move toward each other, and warmer air is pushed upward. Occluded fronts bring cool temperatures with rain or snow.
Low pressure areas bring cloudy and rainy weather. Rapid changes in low-pressure area cause storms. Three types of violent storms include thunderstorms, tornadoes, and hurricanes.
Thunderstorms- very intense rainstorms with thunder, lightning, strong winds, and sometimes hail
Lightning- when an electrical spark is generated from either a cloud to a cloud, cloud to the ground, or ground to a cloud.
Tornado- an extremely violent storm, consisting of a funnel or rope-shaped cloud which hangs below a cumulonimbus cloud.
Hurricane- a large, violent storm created over water.
Hurricane Floyd caused severe flooding, and severely damaged the coastal plain of North Carolina in 1999.
Gulf stream- ocean current flowing along the coast of the EasternUnitedState, up toIreland and Great Britain.
Hurricane Katrina hit Mississippi and Louisiana in August 2005. It was the worst hurricane to ever hit the U.S.
Meteorologists are scientists who monitor weather conditions.
Meteorologists use a synoptic weather map to forecast the weather.
Statistical forecasting is based on finding patterns or trends in weather.
Weather forecasting depends on sophisticated technology that gathers information from all across the nation.
Weather map- meteorologists use different lines and symbols to represent different types of weather
Thermometer- used to measure air temperature
Barometer- used to measure air pressure
Wind vane- measures the direction of the wind blowing
Anemometer- measures wind speed
Hygrometer- measure humidity
National Weather Service- where all weather information collected from weather satellites and radars is sent
Radar- uses radio waves to measure the distance and location of weather such as rain
Weather- the day to day atmospheric conditions in a certain area
Climate- the average weather conditions in a certain area over a long period of time
Temperature and Precipitation are the two most important factors in determining climate.
Three major climate zones in each atmosphere
- Polar- located around North and South Poles, very cold climates
- Temperate- “mid-latitudes”, moderate temperatures neither very cold or very hot
- Tropical- very mild temperatures year-round
Distance from the equator determines precipitation patterns.
Orographic precipitation- when moist air rises to the top of a mountain, the air cools, new water condenses as rain or snow and falls on the windward or top of mountain.
Rain shadow- the leeward side of the mountain that receives dry and warming air
Large bodies of water and ocean currents also influence climate.
Sea breezes- help keep the temperature down near the coast
Ocean currents are like massive rivers within the ocean.
Warm Ocean Currents get their power from 3 main sources:
- Heat from the sun
- Strong winds
- The spinning of the Earth on its axis
Cold Ocean Currents run deep below the surface of the ocean, where the water is not warmed by the sun. As winds blow warm surface water out to sea, the cold water fills in the gap.
Jet stream- the fast moving narrow zones of air in the troposphere which blow from the west to the east due to the earth’s rotation.
Valley breeze- warm air that rises and flows up the mountains during the day
Mountain breeze- cool air that sinks and flows down the mountains at night
Understanding Force and Motion
Inertia- the tendency of a motionless object to remain motionless
Force- a push or pull on an object
Gravity- the force that pulls objects toward the Earth
Friction- an object’s resistance to move, this is created whenever two surfaces touch
Lift- an upward force that is able to overcome the downward pull of gravity
Drag- similar to friction, only in the air
Aerodynamic designs reduce drag.
Thrust- a forward force produced by an engine
Motion is measured in terms of speed.
SPEED= Distance traveled
Time it takes to travel that distance
Velocity- the measure of speed that takes into account the direction of the movement
Acceleration- is a measure of the rate of change of an object’s speed
Acceleration= speed
Time
Slope- the distance covered while coming down fro a height is called slope
Gravity does not care about mass. The increase in acceleration is the same for all objects as they fall closer and closer to the earth.
Work is done when a force moves an object.
Energy- the ability to do work
Work that goes into a machine is work input. The work done by a machine is work output.
There are six types of simple machines:
- Inclined Plane- ramp, the simplest machine of all
- Wedge- an inclined plan that moves through an object
- Screw- an inclined plane that is wrapped around a cylinder to form a spiral
- Lever- a bar that pivots around a fixed point
- Wheel and Axle- made up of a large circle and smaller circle
- Pulley-changes direction in which you have to apply force, made up of a rope and a wheel
Unbalanced Force- when the total force on an object is moving in one direction, changes the motion of an object
Balanced Forces- forces exerted in opposite directions and are equal in size, no change in motion
Newton’s Three Laws of Motion:
First Law of Motion- “Law of Inertia”, An object with no unbalanced force acting on it will wither remain at rest, or continue moving at constant speed in a straight line unless a force acts on it.
Second Law of Motion- “Law of Acceleration”, when an unbalanced force is applied to an object, the object accelerates. Also, the greater the force the faster the object moves.
Third Law of Motion- For every action, there is an equal and opposite reaction.
Ecosystems
Ecology- is the branch of science that studies how living things interact with one another and with their environment. All the plants and animals living in a given area, together with the nonliving parts of the environment, make up an ecosystem.
Abiotic- nonliving factors of an ecosystem include soil, water, climate, and sunlight.
Biotic- living factors of an ecosystem that include plants, animals, and other living organisms.
Ecosystems are typically self-sufficient and independent of other ecosystems. Any group of living and nonliving things interacting with each other can be considered an ecosystem.
Estuary- is a partially enclosed body of water where seawater and fresh water meet and mix. Examples include: bays, mud flats, swamps, and inlets.
Life in an estuary is influenced by the rise and fall of the tides.
Mammals birds, fish, reptiles, shellfish, and plants all live and interact in this ecosystem to create very complex food webs.
The soil, sand, and mud in an estuary are full of rich decaying matter in which plants thrive. During the day, when the tide is out, creatures such as clams and oysters close their shell for protection. An estuary comes “alive” at night when the tide returns. The returning seawater (high tide) floods the estuary bringing protection from predators.
Estuaries also act as natural buffers between the land and the ocean. They protect the mainland and people from the major force of heavy storms.
Salt marshes- occur in places where the land meets the sea, such as barrier islands and other coastal areas.
Salinity-salt content (amount of salt in the water) depends on whether it is located close to the ocean or further upstream in the estuary. The water level and salinity level determine which plants and animals make their homes there.
Microscopic organisms like bacteria, fungi and algae make their home in the decaying marsh grasses. The plants of the salt marsh provide shelter from predators, especially for young animals who use the salt marsh as a nursery.
Oceans- cover three-quarters of the Earth’s surface.
Pond- is a body of water shallow enough to allow plant roots to reach the bottom.
Lakes- bigger than a pond and is too deep to support plant roots except near the shore.
Biosphere- is the part of the Earth where life exists. The biosphere is characterized by large regions. These regions making up the biosphere are called biomes.
Temperature- is the major factor in determining the biome. This includes not just the average temperature, but things such as the length of the growing season and whether or not it ever freezes.
There are four biomes that extend from the extreme latitudes with low temperatures to the tropics with very warm temperatures. These are the tundra, taiga, deciduous forest, and tropical rainforest. Other biomes are controlled not so much by temperature but by the amount and distribution of rainfall.
Deciduous forest- is an area with a high density of trees.
Photosynthesis- allows trees to capture energy from the sun and use it to grow. As the chlorophyll in the leaves breaks down, the colors of the leaves are exposed and the leaves change color. To survive the long winters, trees become dormant and drop their leaves. When spring arrives and the days become warmer, the process of photosynthesis begins the cycle again.
Grasslands- are big open spaces with only a few bushes and trees that are found by rivers and streams. These grasslands are often found between forests and deserts. The amount of rainfall that occurs in a grassland is a major factor in its maintaining its characteristics.
Desert- is a land of extreme heat and dryness. Temperatures in excess of 200 degrees Fahrenheit are common.
Tundra- is located at the top of the world near the North Pole. The frigid cold and deep snow makes life difficult in the tundra.
Taiga- is south of the tundra. This is an area of dense evergreen forests of coniferous trees. In the winter, food shortness and coldness make like difficult. Some animals hibernate and others fly south if they can. The average temperature is below freezing for 6 months out of the year.
Tropical rainforest-in the extreme south near the equator and receives plenty of rainfell all year long. An average of 50 to 260 inches of rain falls yearly. Rainforests cover less that 6% of the Earth’s land surface, but produce 40% of the Earth’s oxygen.
Ecosystems are not lush gardens of unlimited resources. There is fierce competition for food, space, and mates.
Niche- is an organism’s “address” in the community. It defines where an animal lives, what it eats and what it gives back to the ecosystem.
Every single organism depends on the sun for survival.
Plants are producers because they provide their own energy.
Animals are consumers because they get their energy indirectly, either by eating animals that eat plants.
Primary consumer-an animal that eats only producers
Secondary consumer- an animal that eats a primary consumer, secondary refers to the fact that the organism is removed from the original source of energy-the plant.
Consumers that eat only plants are called herbivores
Carnivores are animals that eat only other animals.
Omnivoreseat both plants and animals.
When animals die, their bodies return to the soil. Decomposers are organisms in the soil that break down this matter into simple nutrients. These simple nutrients are then used by plants to grow. Fungi, such as mushrooms, and bacteria are examples of decomposers. Decomposers are the recyclers of ecosystems.