ENVS Exam 2: Let's get it
Terms in this set (55)
What drives thermohaline circulation (THC)?
Deep ocean currents are driven by differences in water density, controlled by temperature- (thermo) and salinity (haline)
How are the ocean and atmosphere connected?
Ocean circulation produces heat that influences climate change across the globe
Where does the marine productivity primarily occur and why? What limits it?
Primarily on the thin surface layer of the ocean where the sun easily penetrates the water, the limitations are the growth of Iron, phosphorus, and nitrogen
What and where are the major ocean zones - coastal, intertidal, benthic, abyssal?
-Intertidal - At the edge of land and water. A diverse set of environments such as beaches, mudflats, and rocky coastline.
-Coastal - From the land to the edge of the continental shelf, areas such as coral reefs and mangrove forests. Highest biodiversity in the ocean.
-Benthic - At or near the ocean floor. A
diversity of animals such as seaweed, bacteria, and animals live there.
-Abyssal - Deepest parts of the ocean floor with high pressures and cold temperatures. Bacteria and fish survive by organic matter that falls from the surface of the ocean. Some areas surround hydrothermal vents that release sulfur which provides chemical energy versus energy from the sun to build organic molecules.
How are ocean temperature, solubility, salinity and density related?
They create 3 layers of the ocean because the denser the water, the heavier it is and sinks.
Mixed Layer - Transition Layer - Deep Ocean
Warm waters at the top lower its density but it evaporates which increases salinity, therefore density which makes the water sink deeper and deeper.
How do phytoplankton impact us?
As the planet warms, phytoplankton production increases, leading to Dimethyl Sulfide emissions, increasing DMS flux then leads to increased production of SOx and CCN (negative feedback)
Phytoplankton photosynthesize using energy from the sun, producing organic carbon.
Why are coral reefs special and why are they threatened?
Coral Reefs are special because they support nearly 25% of the world's fish species and other marine animals. The economic value of coral reefs is nearly $30 billion per year. They are threatened thanks to overfishing, pollution, and climate change.
What are some key differences and challenges between capture fisheries and aquaculture?
They are both industries that capture fish or invertebrate but capture fisheries remove wild populations of fish from marine or freshwater setting while aquaculture involves raising fish in some form of confinement in fresh or marine waters.
Aquaculture has many fish living together in pens so the chance of fish developing diseases is high
How does upwelling work?
It's an ocean current that flows from the deep ocean to the surface ocean. These currents occur when winds or other currents along a coastline or over larger areas of the ocean cause water to flow away from the continent.
How does marine debris/litter impact the ocean?
Animals become entangled or ingest plastic debris, mistaking it for food, and since it can't be digested it leads to starvation.
Where is bycatch high? Why does it happen?
Bycatch is high in any area surrounding a fishery. It happens because endangered species or just marine species in general that were not intended to be caught get hooked or trapped when attracted to the bait
What is sustainable seafood? What are some examples?
Capturing seafood without harming the population of the species. Efforts to make fisheries more sustainable include marine reserves, closure of threatened fisheries, and changes in consumer behaviors.
Colorado is a headwaters state-What does this mean for the ocean?
Colorado is the base for four major rivers that provide water to 18 other states and the republic of Mexico. This means some of our water will flow into the ocean.
How is ocean productivity affected by ENSO?
They cause large-scale atmospheric circulation patterns such as jet streams. El nino also causes the upwelling off the coast of South America to not be as strong. This affects the fishery in this part of the world.
How do solubility and biological pumps work? Are they positive or negative feedbacks?
Solubility pump: colder H2O increases solubility. Warming stratifies water column, reduces transport of carbon, decreases sequestration. Positive feedback.
Biological pump (aka carbonate pump & phytoplankton): global warming à increase in phytoplankton production. Phytoplankton photosynthesis promotes CO2 absorption. Negative feedback.
Compare and contrast the CLAW hypothesis and anti-CLAW hypothesis
-The hypothesis is that as planet warms, phytoplankton production increases, leading to DMS emissions; increased DMS flux then leads to increased production of Sox & CCN.
-Impact: negative feedback - dampens influence of incoming solar radiation, leads to a cooling, and/or masking of warming.
-Anti-CLAW hypothesis: eventual decline in phytoplankton due to stratification.
Where does dimethyl sulfide (DMS) come from and how does it affect us?
-It comes from incoming solar radiation into the atmosphere. It is in the surface water of oceans. This gives the ocean it's salty smell because it is a breakdown of a sulfur containing organic molecule found in some species of phytoplankton.
-One reason why the coast sometimes appears hazy.
Why will sea level rise happen? Think from physics and chemistry perspectives... How do we know this will occur? What will the impacts be?
-Sea level rise is going to happen because of the increased heat levels in the atmosphere causing ice caps to melt and produce more water.
-The impacts would be cities going underwater and the loss of thousands of lives and homes.
El Niño Southern Oscillation (ENSO): What are the distinctions between El Niño and La Niña?
El Nino events are caused by unusually warm water at the surface of the tropical pacific ocean Atmospheric circulation patterns change, with high pressure in the western pacific and low pressure in the east. Trade winds weaken. Warm waters spread from west to east into the central Pacific. .
La Nina events occur when the water is, instead, unusually cold. High and low pressure zones stay neutral and produce strong trade winds. Cool water flows out toward the central pacific and to the coast of South America.
Why is seawater salty?
Salinity; the total mass of salts (sodium and chloride) compared to the mass of the water in which they are dissolved. Also rocks inland are subject to physical and chemical weathering. The ions that are weathered off the rocks then flow into the ocean making it salty.
What are the causes of eutrophication? How does eutrophication lead to hypoxia, creating dead zones?
Eutrophication is a change that can occur in freshwater as the result of adding nitrogen and phosphorus. These nutrients trigger the growth of algae on the surface of the water and as it dies down and sinks to the bottom, bacteria begins to decompose the dead algae, depleting the water of oxygen which leads to an increased amount of fish dying.
Algal blooms block all oxygen from entering
and CO from leaving the water everything dies
How does ocean acidification work and what's driving it? How is pH changing?
When carbon dioxide (CO2) is absorbed by seawater, chemical reactions occur that reduce seawater pH and the saturation states of biologically important calcium carbonate minerals.
As more CO2 is added to the atmosphere, some of it is absorbed by ocean water. It goes through a series of chemical reactions and forms carbonic acid, which releases hydrogen ions which lowers its pH, causing an increase in acidity known as ocean acidification.
How is chemical weathering related to the oceans do?
Atmospheric carbon combines with water to form a weak carbonic acid that falls to the surface in rain. The acid dissolves rocks—a process called chemical weathering and releases calcium, magnesium, potassium, or sodium ions. Rivers carry the ions to the ocean.
The salts in the ocean water mostly come from land through a process called chemical weathering; rocks slowly break down when exposed to water and chemicals in rainfall or even volcanic eruptions and streams and rivers carry the dissolved ions to the ocean
What do the five gyres around the world's oceans do?
How is weather different from climate?
Weather is whatever phenomena that's occurring in the atmosphere in a location at a certain point in time, whereas climate is the average weather in a certain place over a long period of time
How is climate change different from global warming?
-Global warming refers only to Earth's rising surface temperature, while climate change includes warming and the side effects of warming like the melting of glaciers, heavier rainstorms, or more frequent drought.
-Global Warming is one symptom of the much larger problem of human-caused climate change.
How does the Sun distribute energy on Earth
Solar Radiation; energy that comes from the sun, travels through space and into our atmosphere
What is the planetary energy budget? How is it affected by radiative forcing? Think about external (direct/indirect), internal types of forcing.
The planetary energy budget refers to how much energy is absorbed by the surface of the earth and how much is reflected back up into the atmosphere. When energy bounces off of earth's surface it is changed into long-wave radiation which is sometimes unable to go back out of the atmosphere
What are indications of climate change?
General Circulation Models (GCMs); mathematical representations of physical and biological processes that occur in the atmosphere, in the oceans, and on land. Scientists develop equations that describe processes that affect climate, such as how water evaporates from the land surface or how ice reflects sunlight
What is global warming potential (GWP) in relation to atmospheric gases?
When carbon dioxide, methane, and nitrous oxide gets trapped in the atmosphere over a certain period of time is its GWP.
What are examples of high vs low albedos? How does albedo relate to climate change?
-High albedo value indicates high reflectivity. (snow absorbing 5% of incoming light)
-Low albedo indicates low reflectivity (parking lot absorbing 96% of incoming light)
-It is critical to climate because it determines how much energy is reflected back to space and how much is absorbed and then re-emitted in long wave forms that can warm the atmosphere.
How does a gas' residence time relate to climate change?
Different greenhouse gases stay in the atmosphere for longer periods of time, the longer it takes for a gas to leave the atmosphere the risks can be potentially higher
What are some climate related positive and negative feedbacks?
-A positive feedback occurs when part of a system responds to a change in a way that further accelerates or amplifies the change. Such as Greenhouse Gasses providing warmth to our planet.
-A negative feedback occurs when the system responds in a way that slows the change
What are the major glacial/interglacial periods in our history? Where are we now?
-For the past 12,000 years, including to this day, we have been in an interglacial period known as the Halocene. Relative warmth and climate stability.
-Medieval Warm Period; C.E. 900 to 1300
-Glacial period; ice age.
-"Little ice age"; 1450-1850
Compare and contrast infrared radiation to incoming solar radiation
-Infrared Radiation: Long waves of radiation absorbed by the sun and then traps and reradiates as longwave(heat) radiation.
-Solar Radiation: Absorbed into the atmosphere but some reflects back into space.
What are characteristics and properties of our major greenhouse gases? Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), Tropospheric ozone (O3), Chlorofluorocarbons (CFCS), Hydrochlorofluorocarbons (HCFCs), Water vapor (H2Ov)
Long Lived in atmosphere -
-Carbon Dioxide (CO2): Emissions of carbon from both fossil fuel combustion and deforestation .Rise in CO2 concentration is due exclusively to human activities.
-Methane (CH4):Emitted naturally from very wet soils, as well as during natural gas production and transport, as well as from livestock. Rise is largely due to humane activity.
-Nitrous Oxide (N2O): Emitted from an increased use of nitrogen fertilizers in agriculture, combustion of fossil fuels, and release of this gas during some industrial processes.
Short Lived in atmosphere -
-Tropospheric ozone (O3):
-Chlorofluorocarbons (CFCS): Artificial compounds that were not present in the atmosphere prior to the 1900s.
- Hydro Chlorofluorocarbons (HCFCs):
- Water Vapor (H2O): Flows quickly into and out of the atmosphere but are important because they influence the flow of energy through the atmosphere
How does the greenhouse effect work?
Without greenhouse gases, the earth would be too cold to inhabit. It's a mixture of different chemicals in our atmosphere
What was the outcome of the Montreal Protocol?
197 nations and the European Union agreed to phase out the use of CFCs and to replace them with chemicals that are less harmful to stratospheric ozone
What factors influence the Earth's climate?
Greenhouse gases and aerosols, land-use changes, solar radiation
What are radiatively active gases and what does that mean?
They are some gases and particles that can absorb incoming solar radiation or outgoing infrared radiation. They are radiatively active because of the way they interact with different forms of energy in the atmosphere which alters heat.
What are some differences and examples of climate mitigation and adaptation?
Mitigation: Taking steps to reduce or eliminate causes of climate change. Such as reducing emissions of greenhouse gases by increasing energy efficiency, reducing energy use, and switching to energy technologies that don't produce greenhouse gases.
-Adaptation: Taking steps to reduce the risks associated with climate change. Such as relocating population centers and building sea walls or other structures to prevent flooding and distribute fresh water. Requires more resources and money.
How we use proxy data to know what we know about past climate? (e.g. pollen records, ice cores)
We can take a group of greenhouse gases that include CFCs and analyze them to gain an understanding of ancient air and greenhouse gas concentrations. Such as drilling into ice cores.
How do we use models to know what we know about climate projections?
By determining the future of greenhouse gas emissions
What are Milankovitch cycles and how do eccentricity, axial tilt, and precession affect climate?
-Variations in position of the sun in relation to the Earth over an extended period of time.
-Eccentricity: measure of the shape of Earths orbit around the sun. 100,000 year cycle.
-Axial Tilt: measure of the position of the earth's equator relative to the sun. 41,000 year cycle.
-Precession: a wobble in the rotation of Earth on its axis that affects the orientation of earth relative to the sun. Wobble varies about 23,000 years.
What are aerosols and how do they affect climate?
-Aerosols are both naturally occurring and human-produced particles.
-Mineral aerosols cause black carbon which because of their dark color (coal combustion, forest fires) they tend to absorb light and warm the temperature.
-Sulfate aerosols tend to cool the climate. Emitted during coal and diesel combustion but are also produced naturally by phytoplankton in oceans and volcanoes.
Who makes up the Intergovernmental Panel on Climate Change (IPCC) and what do they do?
900 scientists who study projections for and potential impacts of climate change
How does CO2 (in parts per million) change through time and seasonally as shown in the Keeling curve?
Up until the 1800's, it was pretty steady but had a massive incline towards the 1900's.
What did Svante Arrhenius discover?
First scientist to predict that rising concentrations of gases such as CO2 would cause the atmosphere to warm. Also predicted that combustion of fossil fuels would cause global temps to rise.
What did Guy Stewart Callendar discover?
First to discover that the planet has warmed
What did Jean-Baptiste Joseph Fourier discover?
What factors determine the Earth's temperature and climate?
What did Frederick William Herschel discover?
Do the varying brightness of stars to bring changes in the temp on earth
What did John Tyndall discover?
How are some gases trapped in the atmosphere while others are not
What did Norman Borlaug do?
How does the Carbon cycle work? Where is most carbon found?
Largest reservoir of carbon is in carbonate rocks, lithosphere.
What are biogeochemical reservoirs and what are some examples?
he location of molecules, where they spend their residence time. Lithosphere, atmosphere, biosphere, hydrosphere. A location where biogeochemical resources are found that participate in biogeochemical cycling.