Scientific Method
Steps
Conclusion
Using from what you experienced from your outcome, include your statement on whether it accepts the hypothesis or rejects it. Use recommendations to further improve your experiment and to study more about it.
Collect & Analyze Results
Change the procedure when needed. Confirm the outcome by retesting. Record your outcome using graphs, tables, photos, etc.
Materials
Include a detailed materials list.
Procedure
Develop and follow the desired procedure.
Hypothesis
Predict an answer to your problem or question. A hypothesis is an educated guess about the independent and dependent variables.
Dependent Variable
A factor that might be changed as a result of the independent variable changes. The dependent variable, however, must be measured.
Independent Variable
A factor that can be controlled or changed during an experiment. Valid experiments have only one independent variable.
Observation/Research
We make our observations and research our topic based on the experiment.
Problem/Question/Purpose
When we develop a specific question or problem, we can solve it using experimentation to see the outcome.
Chemistry
Common Indicators
Bromothymol blue
Phenolphthalein
Cabbage juice
pH paper
Blue litmus
Red litmus
Indicators are chemicals that turn into different colors when added to an acid or base
Acids & Bases
pH scale
A neutral solution has a pH of around 7 (e.g, pure water)
A basic solution has a high pH (typically above 7)
An acidic solution has a low pH (typically below 7)
The pH scale also measures how many hydrogen or hydroxide ions are there in the solution
The pH scale is a measurement scale used to determine how acidic or basic a solution is
Bases
Cabbage juice turns in a blue-green color
Orange methyl turns in a yellow-orange color
Blue bromothymol turns blue
The colorless pheno turns pink
Red litmus turns blue
pH of more than 7
Feels slippery and soapy
Tastes bittery
Compounds which dissolves in water to porduce hydroxide ions in solution
Acids
Properties
Indicators
Orange methyl turns red
Neutral blue bromothymol turns into yellow
Pink pheno turns into no color
Blue litmus turns red
pH of less than 7
Reacts with some metals to produce hydrogen
Tastes soury
Compounds which dissolves in water to produce hydrogen ions in solution
Molecular Compounds
Usually formed between 2 or more nonmetals; also referred to as covalent compounds
A type of compound formed when two or more atoms of different elements share electrons
Polyatomic Compounds
Polyatomics are groups of atoms that are stable and have a net charge
Ionic Compounds
Non-metals gain electrons to form into negative ions as a result
Metals lose electrons to form positive ions as a result
Ionic compunds will result when nonmetals take electrons from metals
Atoms and Ions
Ions
Charged atoms or molecules
Cations = positive ion
Anions = negative ion
Periodic Table
Atomic mass - indicates the total number of protons and neutrons (e.g, flourine; 10 neutrons + 9 protons = 19 (atomic number))
Atomic number - represents the number of protons, and also the number of electrons in a neutral atom. Since each atoms have different amounts of protons, the atomic number is used to order the elements. (e.g, chromium = 24)
Atomic symbol - abbreviations which are used for elements in the periodic table (e.g, zinc = Zn)
Parts of an Atom
Subatomic Particles
Electrons - has a negative charge, found circulating the nucleus through shells, and does not weigh a specific amount
Valence electrons - the outermost electrons in the outermost/largest shell
Neutrons - has a neutral charge, also found in the nucleus, and weighing a specific amount
Protons - has a positive charge, found in the nucleus, and weighing a specific amount
Orbitals/Shells - areas around the nucleus which contains electrons that circulate around it
Nucleus - the center of the atom which consists of protons and neutrons
Classification of Matter
Solutions
Solution - a mixture which has the solute already dissolved in the solvent
Solvent - the liquid that will dissolve that solid substance
Solute - a solid substance which is dissolvable in liquid
Three Kinds of Matter
Mixtures
Hetrogeneous
These mixtures are easy to tell the differences between the substances in them, and they are easy to seperate.
Homogeneous
These mixtures are not easy to tell the differences between the substances in them, and they are really difficult to seperate. They are also referred to as solutions.
A substance made of two or more other substances which are not chemically combined
Compounds
A substance made from two or more elements which are chemically combined together
Elements
Substances that cannot be broken down or made from any other substances. Always mentioned in the periodic table (e.g, oxygen, sulfur, lead, gold)
Properties of Matter
Flammability (how easily does it catch on fire)
Viscosity (depends on the speed of the flowing liquid)
Density (how dense is it)
Odor (does it emit a smell)
Temperature (hot or cold)
Strength (weak or strong)
Hardness (hard or soft)
State of Matter (solid, liquid or gas)
Texture (e.g, soft, smooth...)
Color (e.g, red, blue...)
Safety and Lab Equipment
Lab Equipment
Other Equipment
Wire Gauze
Usually placed between the bunsen burner and another equipment piece
Crucible & Cover
Used to heat specific substances to remove water and then dry them
Watch Glass
Used to hold small quantaties of liquids or to cover an evaporating dish to prevent splattering
Evaporating Dish
Used to evaporate liquids in a solution
Scoopula
Used to transfer solid substances, looks similar to a spoon
Mortar & Pestle
Used to grind solid material into smaller pieces
Petri Dish
A small, shallow dish made of glass or plastic with a loose cover. Used to hold a culture medium in which bacteria, fungi, germs, etc can be grown
Thermometer
A measurement tool used for determining the temperature, and also measures in Celsius
Test Tube Brush
Used for cleaning test tubes. They are located in beakers which are near to each sink.
Goggles
Protective eyewear surrounding the eyes. Used to protect them from impact, dust, splashes, heat hazards, etc.
Bunsen Burner
A common piece of laboratory equipment that produces a single flame. Used to heat substances for 100 degrees Celcius and higher
Triple Beam & Digital Balances
Triple beams are used to measure the masses; the reading error is 0.5 g. The mass ranges for balances are between 1g to 610g. Digital balances are used for measuring masses more accurately. The mass ranges for balances are between 0.5g to 600g.
Forceps
Used for pulling something, or for picking up objects which are too small to be handled
Thermometer Clamp
Used to hold thermometers on ring stands
Ring Stand & Clamp
A metal stand used containing a long, upright rod attached to a rectangular base. Used for supporting laboratory equipment
Tongs
Used for lifting containers that contains high temperature chemicals
Pipette
Used to transport a small quantity of a liquid
Funnel
Used to pour liquids into containers which have small openings
Test Tube Rack
Used to hold 6 or 12 test tubes
Glassware
Non-Volumetric Glassware
Test Tubes
A lipped tube mainly used for heating, mixing or holding small amounts of solid or liquid chemicals
Erlenmeyer Flask
These flasks are useful for mixing liquids by swirling them using a hand holding the neck. Like beakers, they are also marked "graduated" on the side to indicate the approximate volume of their contents. Erlenmeyer flasks are not appropriate for measurement accuracy.
Beaker
A glass that consists of a wide mouth and a lip for pouring. Their sizes range between 50 and 1000 mL. Their main usage is for holding, mixing and heating liquids. They can also be used to transport liquids to another container. They are marked "graduated" on the side to indicate the approximate volume of their contents. Beakers are not appropriate for measurement accuracy.
Volumetric Glassware
Graduated Cylinder
Used for accurate measurement
Used to measure liquids' volume ranging from 10 - 100 mL
A tall, narrow glass container with a volume scale
WHMIS (Workplace Hazardous Materials Information System)
HHPS Symbols (Hazardous Household Product Symbols)
WHMIS Symbols
Environment
May cause damage to the aquatic environment
Health/ozone layer hazard
May cause extreme ozone damage
Less critical health hazards
Explosive
Explosive hazard
Extremely reactive
Corrosive Materials
Avoid getting in contact with or inhaling
Can burn metals, skin or eyes
Biohazardous
Avoid contamination
May cause serious diseases resulting in illness or death
Health Hazard
May cause cancer, birth defects or sterility
Poisonous over long-term exposure
Poisionous & Infectious: Acute
May burn eyes or skin
Can cause death if exposed to small amounts
Oxidizing Material
Keep away from open flames as well as combustable materials
Fire/explosion risk
Flammable & Combustible
Store in a cool area
Flammable can cause fire at lower temperatures than combustible materials
Fire hazard
Compressed Gas
Do not puncture, drop or place it near a heat source
Explosion danger
Contents are under pressure
Biology
Cancer
Preventing Cancer
Get vaccines to reduce your chances of developing cancers later in life.
Make healthy choices - avoid tobacco, limit alcohol usage, protect your skin from UV, eat a healthy diet, maintain a healthy and appropriate weight and be more active
Early detection of cancer is important. Cervical, breast and colorectal cancer screening as well as a self-exam for testicular cancer.
Two Tumor Types
Malignant (cancerous) - has the ability to spread to other parts of the body
Benign (non-cancerous) - does not spread, although it can sometimes be malignant
Statistics
Breast cancer is the most common in females
Prostate cancer is the most common in men
Lung Cancer remains as the leading cause of death for both men and women
According to incident rates in 2009, it is estimated that 40% of Canadian women and 45% of men will develop cancer during their lifetimes.
1 in 4 deaths are caused by cancer
What is cancer?
There are over 100 different types of cancer.
Unlike other infectious diseases such as flu or the coronavirus, cancer is not contagious.
Cancer can form and develop anywhere in the body, and it can also happen at any age.
Cell Organelles
Vacuoles
Supports the cell shape in plants
Functions as the storage room for water, food, enzymes, waste, etc
Many smaller vacuoles are part of animal cells
Large, centred vacuoles are usually in plant cells
Cell Wall
Made of celluose
Located outside of the cell membrane
Found only in plant and bacteria cells
Functions as a protective barrier for the cell
Chloroplast
Converts sunlight into food such as glucose
Consists of a green pigmnt; chlorophyll
Found only in plant cells and algae
Mitochondria
Changes energy which are stored in food to energy the cell needs; ATP
Site of celluar respiration
Functions as the powerhouse of the cell
Lysosomes
Consists of digestive enzymes which breaks down waste
Functions as the trash disposer of the cell
Golgi Apparatus
Distributes and transports molecules through the vescicles
Collects, modifies and packages cell molecules
Functions as the delivery packaging system of the cell
Endoplasmic Recticulum
Smooth ER has no ribosomes; it produces horomones and lipids instead
Rough ER is covered with ribosomes; site of protein synthesis
Transport the system for materials in the cell
Ribosomes
Two types
Found in plant, animal, and prokaryotic cells
Free ribosomes float freely in cytosol
Bound ribosomes are attached to rough ER
Makes the proteins based on DNA instructions
It is not surrounded by a membrane
The smallest organelles
Nucleus
Found in plant and animal cells
Also consists of the nucleolus inside, which produces ribosomes
Surrounded by the nuclear membrane
Stores and keep DNA
Controls the center of the cell
Cell Membrane
Found in plant cells, animal cells and prokaryotic cells
Also known as Plasma Membrane
Absorbs nutrients in and lets waste out
Surrounds the cell and determines what comes in and goes out
Two Cell Types
Eukaryotes
Two Main Types of Eukaryotic Cells
Plant Cell
Animal Cell
Consists of Membrane Bound Organelles
Consists of a Nucleus
Prokaryotes
No Membrane Bound Organelles
No Nucleus
Microscopes
Parts of a Microscope
Base
Light
Fine Focus
Diaphragm
Coarse Focus
Stage Clips
Stage
Objective Lens
Arm
Revolving Nosepiece
Body Tube
Eyepiece
Types of Microscopes
Transmittion Electron Microscope (TEM)
TEMs also use electrons, however, instead of scanning the surface, electrons are passed through thin specimens.
Scanning Electron Microscope (SEM)
This special microscope allows scientists to view a world too microscopic to be seen through a light microscope. SEMs do not use light waves; instead, they use negatively charged electrons to magnify at up to two million times. SEMs can also view specimens in 3D, but cannot view living specimens, as this might kill them.
Stereoscopes
Much like binoculars, this microscope uses two-eye lenses to view larger specimens. Their lenses usually magnify 10x to 20x, but they can also be usable for larger specimens. They can even create 3D specimen views.
Light Microscopes
These microscopes are mostly used in schools, and uses compound lenses to magnify objects. The lenses refract light to make the object beneath them appear a lot closer. Their common magnifications are 40x, 100x and 400x.
Human Body Systems
Skeletal System
Protects and supports the organs, and producing red and white blood cells.
Marrow
Joints
Bone
Immune System
Protects the body from invaders, such as viruses
Bone marrow
Spleen
Lymph nodes
Antibodies
T-cells
White blood cells
Urinary System
Eliminating waste from blood
Urethra
Anus
Rectum
Kidneys
Bladder
Nervous System
Controls the senses as well as direct other systems
Spinal cord
Nerves
Brain
Digestive System
Break down food, absorb nutrients and eliminate waste
Intestines
Pancreas
Liver
Stomach
Esophagus
Respiratory System
Exchange carbon dioxide and oxygen
Trachea
Lungs
Mouth
Nose
Circulatory System
Responsibilities
Transport and distribute nutrients, oxygen and waste throughout the entire body
Major Parts
Veins
Arteries
Heart
Blood
Specialized Cells
Clilated Cells
The cilia sweeps the mucus with trapped dust, and the bacteria backs up the throat
They consist of lots of cilia, which are tiny hairs
They line all the air passages in the lungs together
Their main purpose is to prevent lung damage
Palisade Cells
Consists of chloroplasts around it to help produce plant food
It is relatively tall and has a large surface area to absorb nutrients
It is found in the top of a leaf
Its main purpose is to photosynthesize
Root Hair Cells
A thin cell wall makes it easier for minerals to pass through
Consists of a large surface which helps it absorb water and other nutrients
Always found in a plant root
Its purpose is to absorb
Nerve Cells
Their main purpose is to carry nerve impules to different parts of the body
They have the ability to carry electric signals
They have connections at each end
They have a long length
Sperm Cells
The head consists of enzymes inside it which allows the cell to digest into an egg cell and join with it.
It's found in the testes
A single sperm is relatively small in size and has a long tail which provides movement, so it can swim and find the egg cell
Its main purpose is to fertilize eggs
Egg/Ovum Cells
These cells consists of a yolk which contains food storage for the new cell being formed
Egg cells are usually bulky and large
It is found in the ovaries
Its purpose is to fertilize
Red Blood Cells
Consists of no nucleus, which increases surface area
Consists of hemoglobin, which joins with oxygen
Large surface area for oxygen to pass through
Found in blood
Carries oxygen
Mitosis
Cytokinesis
The cell membrane is then pinched down in the middle. As a result, the cell splits into two. Each daughter cell ends up with the identical set of chromosomes as well as half of the organelles.
Telophase
The chromosomes begin to stretch outwards and lose their rodlike appearance. A new nuclear envelope eventually forms around each region of chromosomes.
Anaphase
The centromeres then split into two and the two chromatids seperate from each other. One chromatid is attached to its spindle fiber while the other shifts to the opposite end. The cells stretches out while the ends are being pushed apart.
Metaphase
The chromosomes then line up across the cell. All of them are attached to each spindle fiber as its centromere.
Prophase
The chromatin from the nucleus begins to condense into chromosomes. The centriole pairs then move to different sides of the nucleus. Spindle fibres begin to create a bridge between the cell ends. The nuclear envelope begins to break down.
Interphase
The cell grows to a bigger size, makes a DNA copy, and gets ready to divide into two cells. Two centrioles are also duplicated as well.
Climate Change
Lesson #4 - Indicators of Climate Change
Affected Species - According to the IPCC, between 40-70% of all species are at risk of extinction if the global temperature reaches 3.3℃. 35% of frogs, toads, and salamanders are threatened with extinction thanks to climate change. Corals are the earliest animals, compared to jellyfish. They conceal skeletons that remains long after the animals died. As these skeletons began to build up, they eventually formed coral reefs as we know them today. Sadly, Earth had lost 20% of coral reefs thanks to warm water, sedimentation and storm damage.
Climate Change on Wildlife - Polar bears usually walk on ice to find and catch seals, since seals swim too quick for the bears to catch them in open water. But nonetheless, if a seal finds a hole through the ice to properly breathe, the bears can catch them. Less ice causes poor hunting, and makes it more difficult for the polar bears to find their main source of food.
Thermohaline circulation (THC) -Winds drive ocean currents up 100 meters of the oceans surface, but can also flow thousands of meters beneath the surface. The deep-ocean currents are driven by the differences in the water density, which is controlled by the temperature. Melting ice and warm waters can result in changing the flow directions of ocean currents. Ice is frozen fresh water; therefore, if the sea ice, icebergs and glaciers all melt, there will be more freshwater added to the oceans. This can eventually diminish the salt contents of the sea water. Freshwater is less dense than saltwater, so it stays on the surface. At the North Atlantic surface, the dense saltwater sinks, bringing the currents through the deep parts of Earth's oceans.
Ocean Currents - Oceans function as Earth's heating and cooling systems. As the Arctic water temperatures increases, it can lead to more extreme weather as well as devestating consequences.
Melting Ice - As the global temperature increases, Earth's sea and glacial ices begins to melt over time. This can eventually result in consequences other than the polar regions. Melting ice can affect the earth by changing the coastlines and altering the geographical continental coastlines, changing habitats of shoreline animals, plants and micro-organisms, causing the loss of property, reducing fresh water available for communities worldwide, and flooding the land which is above sea level. During the summertime, in the Arctic Ocean, the amount of the ice has decreased to a large extent. Over the last century, the normal leval of the oceans has increased to about 20cm. This can cause glaciers by land to melt as well as increase the water levels as it warms.
Ocean Warming - Convection ocean currents combine the cold and warm waters together. Last century, the oceans' tempratures had increased to 0.6℃, which was a bit less than the increasing air temperatures around that time. However, there are a number of reasons for worrying about the warming oceans. As the water grows warmer, it expands over time. This can eventually cause the ocean levels to rise higher, causing more costal areas at risk for being buried beneath the sea. Warmer water also absorbs less CO2 (as if cold pop absorbs more CO2 than warm pop), so it will be less effective as a carbon sink. Phytoplankton undergo the photosynthesis process and also serves as an important carbon sink. Warmer oceans kill more and more plankton over time; less CO2 is absorbed. Warm water can also create or trigger more hurricanes, which can damage costal areas and kill people.
Floods - When the air temperature quickly becomes warm in the spring, snow can melt very rapidly for rivers and streams to handle the run-off. These seasonal floods damage residential homes, buildings, and even cropland, as they are becoming more common in certain areas across the world.
Wildfires - When the weather conditions is hot and dry over a long period of time, the trees begin to dry, and that they start to lose their leaves as a result. The likelihood of fire begins to grow. However, even though the wildfire frequency is generally low worldwide, compared to other natural disaters such as droughts, it's still increasing. Climate change caused by human activity has had an impact on Australia's destructive wildifires that had recently occured, making the risky conditions which caused widespread burning at least 30% more likely than a world without global warming. Wildfires are also a worldwide phenomenon not only affected by heat and precipitation, but also by wind, humidity or other factors. Researchers had looked at the influences of climate change using a measurement standard, which is known as the Fire Weather Index, which takes all of the factors to help determine the risk and chances of a wildfire at a specific area in a specific time.
Hurricanes - Warmer sea temperatures could increase tropical storm wind speeds, possibly causing more damage when they reach contact with land. Based on categorization and classification, Category 4 and 5 hurricanes are more likely to increase, with wind speeds increasing up to 10%. Areas which are affected by hurricanes are shifting polewards. This is most likely related with expanding tropics due to higher global average temperatures.
Storms - Changes in the frequencies and the severity of storms are one potential effect of the faster increase in the average global temperature and the movement of energy worldwide.
Drought - Droughts are the most severe when they affect specific regions located near deserts. However, recently, there has been a lot of seasonal rain that provided water needed to grow crops and to keep animals alive in many of those regions. Warm temperatures can increase the evapration from soil, making periods with low precipitation drier than they would be in much cooler weather conditions. Droughts can also continue through a positive feedback loop, where the dry soils and decreased plant covers can put an end to rainfall in dry areas. Changing climates can also change atmospheric rivers (thin moisture streams carried in the atmosphere), which can eventually disrupt precipitation patterns in the western US.
Heat Waves - For thousands of years, Earth had experienced severe weather conditions, but they are becoming more frequent, widespread, and a lot more severe than in the past. When this happens, air conditioners are turned on, resulting in a growing usage in electricity, and releasing greenhouse gases into the atmosphere. As the air gets warmer, the soil, lakes and rivers also get warmer. The climatic zone borders can shift.
Lesson #1 - Weather & Climate
Latitude & Climate Zones
The sun's energy is low near the two poles, since the energy hits the surface at a specific area and spreads over a large area
The Sun's energy is more high near the Earth's equator, since it hits the surface directly
Equilibrium
The greenhouse effect is also responsible for Earth not being cold. Without the greenhouse effect, which is needed for life to exist and thrive, the earth's temperature would be 255 Kelvin (-18℃) instead of 15℃ (Earth's average temperature).
If there's no climate system, the Earth would still have an energy equilibrium, but Earth would also be colder.
The balance between the energy absorbed from the sun and the energy released from the Earth makes sure that the global temperature remains relatively constant.
Earth’s Surface Emits Energy
The global temperature stays relatively constant, since this energy is balanced.
The amount of energy radiated by Earth's system is equivalent to the amount of energy Earth's system absorbs from the sun.
As Earth's surface warms up from the sun's energy, it obtains thrmal energy and then converts it into low-energy infrared radiation.
Earth Absorbs Energy From the Sun
When radiation contacts a matter particle, one of these three things happens.
The radiation my be reflected off the particle.
The radiation may be transmitted through the particle.
The particle may gain energy by absorbing the radiation.
Weather Map Key
Warm Front
An edge of a warmer air mass, which divides the two air masses. Moisture and temperature gradients are maximized in the frontal zone.
Cold Front
An edge of a colder air mass, which divides the two air masses and maximizes the gradients of temperature and moisture
Hurricane
A moving cyclone with interlocked contours, which have a strong rotation, and can have a minute max of sustained surface winds of 74 mph and up.
Tropical Storm
A moving cyclone with one or more locked isobars, and has a minute max of sustained surface winds of around 39 to 73 mph.
Low Pressure
A specific area of low pressure in a counterclockwise rotation in the northern hemisphere; clockwise in the south.
High Pressure
A specific area of high pressure in a clockwise rotation in the northern hemisphere; counterclockwise in the south.
Sun & Earth’s Climate System
The climate system is powered by the sun. The energy in which the Earth recieves from the sun interacts with the climate system parts to produce climate zones.
The climate system consists of four compound parts that interact with each other to produce Earth's climate. These parts include:
Biosphere
Consists of plants, animals, microbes or any other living thing
Atmosphere
Consists of the gases surrounding Earth
Hydrosphere
Consists of liquid water, ice, and water vapour
Lithosphere
Consists of Earth's rocky crust, and land surfaces
Factors that Influence Climate
Climate change over time
Over the years, cold and warm periods have impacted Earth's history. While some had lasted over a short period of time, others had lasted for hundreds or even thousands of years. During cold periods, glaciers grew a lot bigger and had spreaded across the oceans. And during warm periods, the ice melted. These periods had negatively affected plant and animal life. Since the beginning of the 20th century, temperatures had been constantly rising across the world. However, it's not officialy clear if global warming is being caused by human activities, such as burning fossil fuels and destroying forests.
Surface of the Earth
The amount of sunlight Earth's surface recieves determines how much atmospheric heating occurs. Darker areas, such as heavily vegetated regions, tend to be as good absorbers, while lighter areas, such as snow or ice-covered regions, tend to be as good reflectors. The oceans slowly absorbs and loses more heat than land. The waters then release the heat into the atmosphere, which is then carried out worldwide.
Effects of Geography
The specific area of where a town or city is placed, and how far it is located from mountains and water areas can help control the wind patterns and the air masses affecting it. For instance, costal areas can enjoy refreshing breezes during the summer, while cooler ocean air moves across the oceans.
Topography
Topography can also change the climate depending on the specific location. For instance, mountain ranges can be barriers for air movement. In the Costal Range, the mountains allow for some condensation as well as light precipitation.
Prevailing global wind patterns
There are six main wind patterns worldwide; three in the nothern hemisphere and the other three in the south. As the seasons change over time, the wind patterns either shift northwards or southwards.
Elevation or Altitude affect climate
As altitude increases, climate conditions usually become colder over time. The life zones on mountains consist of these changes, but snow has the highest elevations.
How can information about climate zones be used?
Climate zones can be pretty useful for gardening and farming because plants can best grow in climate conditions which are found within the native ecosystems.
Factors Affecting Climate
Height above sea level (altitude)
Land formations
Presence of ocean and air currents
Presence of large bodies of water
Distance from equator (latitude)
Weather - conditions in a specific location that usually lasts over a short period of time
Climate - the pattern of the weather in a specific region over a long period of time, but also determines what plants and animals live there
Factors that Influence Weather
Weather Fronts
Jet Streams
Air Masses
The Water Cycle
Koppen-Geiger Classification Categories
Polar
Continental
Moderate
Dry
Tropical
Lesson #2 - The Greenhouse Effect
Anthropogenic Greenhouse Effect
The growing amount of the lower-energy infrared radiation trapped from the atmosphere as a result of rising greenhouse gas levels in the atmosphere due to human activity, which is eventually causing Earth's temperature to grow warmer substantially
Negative Feedback Loop
A self-regulating system that functions in order to get more stable.
For example, in this scenario, the temperature in a heated room reaches a specific limit; the heating is then turned off, and the temperature begins to fall as a result. When the temperature drops down to the lowest limit, the heating is then switched back again.
Positive Feedback Loop
A produces more of B, which in turn produces more of A.
For example: High temperatures causes more water to evaporate into the air and form water vapour.
Water vapour is effective on trapping heat, so that more of the vapour increases the temperature.
For hundreds and thousands of years, greenhouse gases have been an important part of our atmosphere and have also been involved in the natural greenhouse effect.
Greenhouse Gases
Greenhouse gases are any gases in the atmosphere that absorbs lower energy and infrared radiation. The majority of the air is made up of nitrogen and oxygen, which do not absorb the radiation from the surface. Greenhouse gases are trapped in the troposphere, which is up to 16,000 meters above the Earth's surface.
Water vapour
2/3 of the natural greenhouse effect is caused from the water vapour in the atmosphere. The amount of water in the atmosphere can be determined by the temperature, which is about 4%. Water vapour and temperature are both associated by a positive feedback loop.
Nitrous oxide
Nitrous oxide (N2O) is 300 times more stronger than a CO2 molecule as a greenhouse gas, but it has lower concentration. N2O also comes from bacteria that produce it, as well as human sources.
Anthropogenic (Human Influenced) Sources of Nitrous Oxide
Chloroflurocarbons (CFCs)
leaks out of refrigerators/air conditioners
no natural sources of CFCs
Livestock manure
Fossil fuel combustion
Used for nitrogen fertilizers
Methane
In the atmosphere, there is fewer methane (CH4) than CO2, however, it's very strong and powerful. CH4 can absorb and trap 23 times more thermal energy than CO2. It also comes from natural and human sources, and is emitted into the air from plant decompostion and animal digestion.
Anthropogenic (Human Influenced) Sources of Methane
Coal mining and natural gas extractions cause methane to be released into the atmosphere
Landfill/sewage treatment plants - methane is released into the atmosphere as an organic material decay
Agriculture - rice farming, cattle ranching, etc.
Carbon dioxide
Carbon dioxide (CO2) makes up about 385 ppm of the Earth's surface, which represents exactly about 0.0385%. However, CO2 is expected to cause up to a quarter of the natural greenhouse gases on Earth. CO2 molecules also have atoms that vibrate and wiggle in different ways, but can also absorb different types of energy.
Carbon Dioxide & Global Temperature
As the temperature increases, the CO2 kept in plants and oceans get released
Increasing of CO2 levels result to increasing global temperatures due to the greenhouse effect; however, increasing of the temperature can result CO2 levels to grow
Anthropogenic (Human Influenced) Sources of Carbon Dioxide
Deforestation - restrains photosynthesis, which would remove CO2 from the atmosphere; as leftover forest waste decomposes, it becomes greenhouse gases
Burning fossil fuels (coal, gasoline, natural gases), releases CO2
Without the greenhouse effect, which is needed for life to exist and thrive, the earth's temperature would be 255 Kelvin (-18℃) instead of 15℃ (Earth's average temperature)
The climate system moderates Earth's temperature by absorbing and storing energy from the sun and distributes it worldwide. So for that reason, every day and night, the temperature always remain constant.
The greenhouse effect is a natural process that has been occuring for millions of years. The gases and clouds take in infrared radiation that has been emitted from Earth's surface and radiate it in all directions, heating up the atmosphere as well as the surface.
Greta Thunburg - a teenager who wants the world to know about the consequences of global warming
Lesson #3 - Past Climates
EPICA and GRIP
As a result, the data lead to a more complete picture and offered a better understanding of climate change.
The data is then compared with research from the Greenland Ice Core Project (GRIP).
The drilling had reached 3270 meters deep.
The European Project for Ice Coring in Antarctica (EPICA) had gathered climate data from around 800,000 years ago.
Evidence of Past Climates from Sedimentary Rock
In order to get evidence of climates which are older than can be analyzed in ice cores (1 million+ years old), scientists have to examine and analyze rocks. Every year, billons of tons of sediments (rock fragments) wash from the land and gather together in thick layers on ocean floors and lake beds. The hard parts of microscopic sea creatures, like algae and diatoms, as well as pollen from flowers are preserved in these sediments. Over long periods of time, the deposited material becomes pressured and hardened to later form into sedimentary rock.
The Rate of Climate Change
Scientists are stil discussing whether climate change is affected by gradual or by catastrophic changes. But, this question is at the center of a disagreement about whether human activity is the main cause of climate change. However, many climatologists agree that humans are affecting the structure of Earth's atmosphere. This affection may increase or decrease the rate of the climate change progression.
Ways to analyze past climates
Fossils
The remains or traces of living things, which are known as fossils, also provide clues when paleoclimatologists analyze and recreate the past climates. The many types and plentifulness of fossilized remains in each rock layer can help scientists recreate the environment around the time the layer formed, including the climate. Since plants and animals are differently adapted in the environment to where they live, analyzing the fossils can help determine about what the environments looked like millions of years ago.
Ice cores
Evidence of Past Climates Obtained from Ice Cores
The composition of the ice
Water consists of differing proportions of hydrogen and oxygen isotopes. Isotopes are different variants of an atom. Water that consists of oxygen-18 freezes at a much higher temperature than oxygen-16 water. Furthermore, water that consists of oxygen-16 tend to evaporate much quicker than oxygen-18 water. For that reason, the concentration of isotopes in different layers of ice represents the temperature around the time the ice had formed.
The composition of the trapped air bubbles
When water freezes, the tiny air bubbles in the water becomes trapped in the ice. The air pockets allow scientists to study and analyze the greenhouse gases concentration over centuries and thousands of years.
Physical characteristics of the ice
(crystal size and shape)
Characteristics help identify the conditions of temperature and humidity around the time the ice crystals were formed.
Dissolved and particulate matter in ice
(Dust, ashes, salts, plant pollen and other materials)
The frozen samples of these materials gives clues about previous events and conditions, such as volcanic eruptions, meteorite impacts, and wildfires.
Much like tree rings, the layers of snow and ice gather together each year. In order to show the evidence of past climate conditions, scientists use a specific drill designed to drill deep through the layers to extrect long, cylinder-shaped samples which are called ice cores. Scientists then analyze the thickness and the composition of ice in each layer to make speculations about the past climates.
Tree rings
Temperature and rainfall both have an effect on tree growth. The total amount that a tree grows during each season is determined by the size and the color for each annual ring. Dendrochronologists study and analyze the details about the size, color, and the shape of each ring. A wide ring indicates wet and cool weather, which allows trees to grow faster. A thin ring, however, indicates that it was grown in dry and hot conditions, when tree growth is a lot slower. A dark ring indicates the growth during the late summer season, and a light-colored ring means the tree had been grown during the springtime.
People have been studying, recording and analyzing the weather for only a few centuries. But, in order to understand what was the climate like a few centuries ago, scientists have to get creative. Paleoclimatologists are people who study and analyze the past climates.
