enviro 200 test
Definition of climate:
a region's long-term pattern of atmospheric conditions
Global climate change defintion:
changes in Earth's climate. including temperatire, precipitation & other variables
Global warming definition:
an increase in Earth's average surface temp
3 factors that influence the climate the most?
sun, atmosphere & oceans
What is a greenhouse gas?
atmospheric gases that absorb the emanating radiation from earth's surface are greenhouse gases. By absorbing and re-emitting this radiation, they warm the earth's atmosphere and surface, like a greenhouse.
What is a primary greenhouse gas?
carbon dioxide
What are 3 types of cycles that affect the climate long term?
- axial wobble
- variation of tilt
- variation of earths orbit
What happens with a rising acidity in the ocean?
rising acidity = consumption of carbonate ions, inhibits carbonate formation within sea plants and animals
pH values
7 = neutral
0 - 7 = acidic
7 - 14 = basic / alkaline
What is alkalinity?
acid neutralising capacity
- for water, alkalinity includes bicarbonate & carbonate
What is turbidity?
= visible indicator of the presence of "solids" in a water sample.
what compounds make up total solids?
- everything that doesnt evaporate below 110 degrees celcius
- inorganic salts, organic material, insoluluble salts, solulable salts, metals etc.
What are the two solid types?
- undissolved solids
- dissolved solids
what is an undissolved solid?
responsible for turbidity or sediment. Can be isolated by simply filtering
What is a dissolved solid?
responsible for the hardness of water. Dissolved solids specifically refers to samples isolated by drying 180 degrees celcius which removes any bound water
what is a volatile solid?
solids that will burn off at =<550 degrees celcius
- includes a majority of organic compounds
what is a fixed solid?
are those remaining after pyrolysis (burning at 550) and consist largely of inorganic salts. These salts are most directly related to hardness.
What is a settleable solid?
solids that will form if sediment is not stirred up. Can be found by simply allowing the material to sit in an Imhoff cone for an hour.
What are the types of diagrams on which anions and caations can be plotted?
- piper
- stiff
- pie
- depth profile
What is hardness?
defined as the presence of divalent cations
- causes water to form scales and a resistance to soap. Hard water doesnt
Pathogens in water
- total coliforms
- fecal coliforms
- E. coli
water treatments
1. Coagulation
2. Flocculation
3. Sedimention
4. Filtration
5. Disinfection
What is disinfection?
a key barrier against microbes in water
What is the most commonly used disinfectant?
chlorine
What are the goals of wastewater treatment?
- to produce clean waste stream (effluent)
- to produce stablisied solid waste (sludge)
- resource recovery (nutrients, fresh water, electricity)
What are the stages of wastewater treatment?
- preliminary
- primary
- secondary
- tertiary
- sludge treatment (biosolids)
What is the purpose of trash racks:
remove trash (rags, branches & plastics)
what are screens?
bar screens
- purpose is to remove smaller materials
what are shredders?
purpose = grind larger solid to smaller solids
what is a grit chamber
purpose = remove inorganic particles larger than 0.15mm
- protect moving equipment
IPCC
- temp will rise from 3 - 5 degrees
- droughts, floods, snowpack decline & water shortages
- temp extremes = health problems. tropical diseases will move towards polar directions
- sea level rise = floods in coastal wetlands, real estate etc
- ecosystems altered, some will disappear (coral reef bleaching)
El Nino?
- winds weaken
- warm water sloshes to the east
- prevents cold upwelling
La Nina?
- cooling of sea surface temp
What are the water treatments?
- Coagulation (rapid mixing)
- Flocculation (slow mixing)
- Sedimentation (settling)
- Filtration (cleaning)
- Disinfection
What is a rapid sand filter?
- different layers
- removal using physiochemical processes
- needs pretreatment of the water by caogulation - flocculation
- higher backwashing frequency
slow sand filters?
- filter through a 3 - 5 foot deep bed of unstratified sand
- growth in the upper surface of the sand is responsible for the particle and microbe removal
- doesnt need pretreatment bc of coagulation - flocculation
- periodically clean by removing, cleaning & replacing the upper layer of active sand
What is a suspended solid?
particles held in suspension by the natural action of flowing waters
what are colloidal solids?
fine silt that does not settle out of water but remain in suspension
what are dissolved solids?
organic or inorganic molecules that are dissolved into the acqueous phase
what is an organic molecule?
molecules that are made of carbon and hydrogen, and can include other elements.
what is an inorganic molecule?
A molecule not consisting of carbon atoms