Unit 2 - CC Introduction and Impacts Flashcards
Are human-caused atmospheric phenomena climate change?
no, we are talking about natural sources of variation
4 things that are NOT results of climate change?
-hole in ozone layer
-smog/pollution
-acid rain
-ocean acidification
weather or climate?
thunderstorm
weather
weather or climate?
avg # of intense precipitation events per year
climate
weather or climate?
a late spring freeze event
weather
weather or climate?
the average date of the last freeze in spring continues to get earlier
climate
weather or climate?
servere hurricane
weather
weather or climate?
an upward trend in the 30 year average of the frequency and intensity of hurricanes
climate
Climate change doesn’t cause hurricanes or storms to form, it just increases the _____ of it happening.
likelihood/frequency
definition: mixture of gases that hold heat to the surface of the Earth
atmosphere
Without the atmosphere, would Earth be warmer or colder?
colder (drop from 60 to 0 degrees C)
When energy from the sun warms the Earth what are the two options for this energy?
(1) escaping back into space
(2) held by greenhouse gases in atmosphere
What is the main effect of the greenhouse effect?
to warm the Earth’s surface and lower atmosphere
In the Greenhouse effect, what type of radiation is emitted from the Earth’s surface?
infrared radiation
When energy is absorbed and then reradiated by the Earth’s surface, what happens?
it gets more disordered/looses energy and the low energy/infrared radiation can’t escape as well
What are the main steps in the Greenhouse Effect?
(1) incoming, short wavelength radiation from the sun
(2) once Earth is warmed by the sun, all objects radiate heat in the form of long wave infrared radiation
(3) long wave infrared radiation is ABSORBED by greenhouse gases in the atmosphere
(4) when GHG molecules stop vibrating, they are reradiated in ALL directions
What does the strength of the Greenhouse effect depend on?
concentrations of different GHG
How is it possible for the Earth’s energy budget to have a stable temperature?
energy entering = energy exiting
In Earth’s energy budget, what can happen to incoming solar energy?
(1) reflected by atmosphere (6%)
(2) reflected by clouds (20%)
(3) reflected from Earth’s surface (4%)
(4) absorbed by atmosphere (16%)
(5) absorbed by clouds (3)
(6) absorbed by land and oceans (51%)
What are 3 different options for incoming solar energy?
(1) absorption: atmosphere, land or water causing warming
(2) reflected: bounced back into space without causing warming
(3) radiated: passively escapes into space
What is the term for natural and VERY long-term fluctuations in the sun’s intensity? Responsible for ice ages.
milankovitch cycles
What is the main cause of milankovitch cycles?
changes in the Earth’s orbit that in turn changes the Earth’s temperature
About how long are Milankovitch cycles?
100,000 years
What is the main way the amount of incoming solar radiation can change due to changes in Earth’s orbit?
milankovitch cycles
How long ago was the end of the last ice age?
10-15,000 years ago
definition: amount of sunlight (solar radiation) reflected by a surface
albedo
Things with ____ albedo:
-light colored
-reflects more light/energy
-ex: ice, snow, clouds
high
Thing with high albedo reflect ___% of incoming energy while things with low albedo ___% of incoming energy.
80; 10
Things with ____ albedo:
-dark colored
-absorb more light/energy
-ex: water, forest, dark soil
low
Is the sea ice albedo feedback positive or negative?
positive
Describe the sea ice albedo feedback?
warming temperature tends to decrease ice cover and hence decrease the albedo, increasing the amount of solar energy absorbed and leading to more warming
In the sea ice albedo feedback, what happens when ice starts to melt and reveal seawater beneath it?
the albedo decreases and the dark water absorbs more heat further melting sea ice
______ feedback: promotes changes that lead back toward equilibrium
negative
_______: systems that promotes further change toward an extreme (amplification of a stimulus)
positive
What is a common example of a negative feedback (overshoot, undershoot, overshoot behavior)?
predator-prey dynamics
What is a common example of a positive feedback (build, build, build, CRASH behavior)?
labor, avalanche
What is the result of the albedo positive feedback cycle?
snowball earth
Describe what snowball Earth was.
as more ice covers the globe, the planet becomes more reflective, or higher in albedo which further cools the surface for more ice to expand
How can volcanic activity temporarily cool the planet? Can all eruptions do this?
ash can reflect sunlight high in the atmosphere before it even comes close to the surface of the Earth; No, only ones with the right sized particles made out of proper materials
Can small increases in GHGs increase temp?
yes
What is the main difference between the natural and human enhanced Greenhouse Effects?
less heat ESCAPES into space & there is more reemitted heat in the human enhanced Greenhouse Effect, contributing to a warmer Earth
In the ______ Greenhouse effect, equal amounts of energy are coming in and leaving.
natural
In the ______ Greenhouse effect, more energy is coming in than leaving.
human enhanced
What % of the atmosphere is made of GHGs?
less than 0.1% (trace gases)
What are the trace gases?
Carbon dioxide (93%)
Methane (0.4%)
Nitrous Oxide (0.08%)
What are natural sources of Carbon Dioxide?
respiration, volcanoes, decomposition, fires (carbon cycle)
What are natural sources of Nitrous Oxide (N20)?
Nitrogen cycle product, fires, car emissions
What are natural sources of methane?
digestion, geologic leaching, melting permafrost
What are natural sources of fluorinated compounds (F gases, SF6, CFCs, HFCs)?
none, all are synthetic
What are natural sources of water vapor?
water cycle, combustion
What are anthropogenic sources of CO2?
fossil fuel burning (mostly coal), cement curing, land use conversion
What are anthropogenic sources of N2O?
gasoline burning, agricultural fertilization
What are anthropogenic sources of Methane?
mining/drilling, rice farming
What are anthropogenic sources of Fluroinated compounds?
mostly coolants and other industrial chemicals (Montreal Protocol-Kigali)
What are anthropogenic sources of water vapor?
no human causes; mostly natural evaporation / transpiration
Can the insulating power of CO2 be measured? How?
yes, a tank with elevated CO2 will have an established relationship with temperature
What is the base unit for global warming potential (GWP)?
1 lb CO2 = 1 GWP
How many pounds of CO2 is equivalent to 1 pound of CH4?
GWP of CH4 is 21, so 21 pounds of CO2
Is CH4 or CO2 a stronger GHG?
CH4 is 21x stronger than CO2; 1 pound of CH4 provides the amount of warming that 21 pounds of CO2 would provide
What are 2 things that determine GWP of different gases?
(1) how well it aborbs light energy
(2) residence time (how long it remains in the atmosphere)
Compare the residence time of CO2 with that of F gases?
CO2: short residence time; easily sucked in by plants
F gases: long residence time
What is the GWP of CO2?
1 GWP
What is the GWP of CH4?
21 GWP
What is the GWP of Fluorinated gases?
7000 GWP (average #)
What is the GWP of Nitrous Oxide?
298 GWP
What GHG has the strongest GWP?
fluorinated gases
Rank the GHGs solely in terms of GWP values:
(1) F gases
(2) N2O
(3) CH4
(4) CO2
(5) water vapor
1 pound of F gas is equivalent to how many pounds of CO2?
7000 pounds
Why is water vapor so low in GWP?
it has a low residence time & moves quickly in and out of the atmosphere
When looking at climate impact, what else other than GWP needs to be considered?
the quantity of gas
What is the order of climate impact of GHGs when looking at GWP x quantity of a gas?
(1) water vapor
(2) CO2 (64%)
(3) CH4 (19%)
(4) F gases (11%)
(5) N2O (6%)
What anthropogenic GHG has the highest contribution to climate warming?
CO2 (64%)
Does warm air hold (more/less) water vapor?
more
Does warm water hold (more/less) dissolved gas CO2?
less
Describe the water vapor feedback cycle.
(1) increased CO2 concentration warms the air in the atmosphere
(2) warmer temps increase evaporation and water vapor in atmosphere
(3) increased greenhouse warming from water vapor
What happens in particular when water warms up in the water vapor feedback cycle?
dissolved CO2 in water will go up into the atmosphere
Describe the ocean CO2 feedback cycle.
as CO2 increases, it increases the warming potential of the atmosphere & if air temperatures warm it also warms the water temp which reduces CO2 solubility and releases it into the atmosphere
Describe permafrost feedback.
when the organic matter in permafrost thaws and decays it leads to an increase in atmospheric CO2 and methane which increases surface temperature
Can the ocean CO2 feedback cycle stop ocean acidification?
No, but it can slow it down
Where is the fastest warming occurring on the planet?
in the Arctic/Northern Poles
Why do the Northern poles warm much faster than the equator?
mainly due to Arctic sea ice decline
Where temperatures are warming the faster is not the same as where temps. are highest? Prove this.
fastest: North pole
highest temp: equator
How do we know about what happened with climate change in the past?
proxy data
Proxy data is data that we can collect to infer something else (that we can’t measure) based on what?
an established relationship (ex: CO2 and temperature)
definition: preserved physical characteristics of the environment that can stand in for direct measurements
proxy data
What are some natural recorders of climate variability when collecting proxy data?
corals, pollen, ice cores, tree rings, caves, ocean and lake sediments, otoliths
How can we infer past relationships between proxy data and climate?
by examining current relationships and then back casting
Are climate and carbon highly correlated in history? How do we know this?
yes; measured data matched proxy data
How are ice cores used to measure CO2?
there are bubbles trapped in really old ice & the gas trapped inside them can be captured and measured
Even though our current ppm levels of CO2 are much higher than historically, what is the real issue?
the fast rate of warming
What was the pre-industrial concentration of CO2 in ppm?
280 ppm
What was the atmospheric CO2 levels in January of 2023?
419 ppm
When was our second warmest March since 1890?
March 2019
How much faster is todays rate of increase than when the last ice age ended?
100x
What months have the highest concentration of CO2?
April/May
Why does April & May have high concentrations of CO2?
-leaves fall off trees but are frozen and can’t decompose, so they wait until the spring for decomposition to take place
-this decomposition releases CO2
-during this time, no photosynthesis is taking place so no CO2 is being pulled out of atmosphere by plants
-water heats up, releasing dissolved CO2 into atmosphere
-higher temps = more respiration
Which months have the lowest concentrations of CO2?
September
Why does September have the lowest concentration of CO2?
-very end of the growing season & photosynthesis happens all summer (plants drawing in CO2); throughout whole summer, photosynthesis gradually declines CO2 levels
The concentration at any given time of CO2 is a product of the past. CO2 accumulates or is drawn down over _____.
time
What is the Keeling Curve?
daily record of global atmospheric CO2 concentration & famous indicator of CO2 change from Hawaii
What is the main piece of info we gather from the Keeling Curve?
annual cycle of CO2 is gradually increasing
Does atmospheric CO2 concentration rise (slower/faster) than emissions of CO2? Why?
slower
-some goes into ocean through diffusion
-some is captured by trees for photosynthesis
How much % of CO2 emissions actually stay in the atmosphere?
50%
_____ where the CO2 is made
sources
Where does CO2 come from (sources)?
-fossil fuels & cement (91%)
-land use change (9%)
______ where the CO2 goes
sinks
Where does CO2 go (sinks)?
-atmosphere (50%)
-land (26%)
-oceans (24%)
With sources and sinks, which has to be larger for CO2 concentration to rise and increase temperature?
sources > sinks
____ model shows predicted temperatures of the future (as a range of possibilities)
climate
What is the biggest source of uncertainty within GCM projections?
human activity
What do climate models make their predictions based on?
“emissions scenarios” or RCPs (these hopefully capture the range of human behavior)
What is the value for high RCP and what does it mean?
8.5; humans will do nothing differently and continue on the current trajectory of CO2 emissions
What is the value for medium RCP and what does it mean?
4.5 & 6.0; we will reach peak emissions by 2050/2070 and then the atmospheric concentration of CO2 would need to start coming down
What is the value for low RCP and what does it mean?
2.6; humans take immediate action to reduce emissions and start to implement Carbon capture technologies that take CO2 out of atmosphere and put it elsewhere
What is the estimate for the average global temp to increase by 2100 (a range)?
1-4 degrees C
Climate change is not just changes in temp but changes in what two others things.
(1) changes in average surface temperature - EVERYWHERE gets at least a little hotter
(2) changes in average precipitation - NOT everywhere will receive less rain
What effect does climate change have on precipitation?
changes WHERE and WHEN precipitation will fall
What are the 3 unique changes to precipitation with climate change?
-more episodic (less frequent rain events)
-more intense (more precipitation in heavy rain events)
-increase in BOTH droughts and flooding
With climate change, places are more likely to receive their annual rainfall over ______ periods of time.
shorter
What is climate changes impact on snow?
less snow; increased probability of wildfires
What is the main way organisms will respond to changes in climate (temp and/or precipitation)?
migration –> they will move across the landscape (different from seasonal migration)
definition: the set of environmental/climatic conditions that an organisms requires in order to survive
climate envelopes
What happens to climate envelopes with CC?
climate envelopes are likely to move around on the landscape
In order to stay within their optimal climatic range, how are species expected to move?
poleward & upward (in elevation)
Which would be easier for animals & plants; moving poleward or upward & why?
upward (because of the condensed fashion of mountains)
-with 1 degree C increase in temp you either move:
(1) 175m upslope
(2) 140km poleward
Where will alpine species go as climate changes? Lowland species?
alpine: find a higher Mountaintop
lowland: up the mountain
definition: the timing of seasonal changes in plants and animals
phenology
What is the result of an earlier spring / longer growing season?
phenology
What are some common examples of phenology?
flowering, migration, calving, molting
definition: when the timing of events for interacting species can no longer co-occur
phenological mismatch
What are 2 great examples of phenological mismatch?
(1) plants & pollinators: plants flower before insects emerge or vice versa
(2) grazers & food availability: migration & plant growth can become out of sync
If an organism can’t migrate fast enough or has phenological mismatch what are their 2 options?
(1) adapt/evolve - this is possible but can be slow and needs a large, genetically diverse population
(2) extinction - can be local or global, some kinds of organisms are much more susceptible than others
