Practice Exam Part 1
how much have N2O levels increased in the atm since 1750?
.06 ppm
why are the atmospheric temp increases since 1750 not attributed to changes in solar radiation
- atm temp increases in troposphere only - need to consider the incr level of greenhouse gases when seeing incr in mean global temperature
major anthropogenic sources for co2
- combustion of fossil fuels - cement production - land use changes such as deforestation
major anthropogenic sources of n2o
- nitrate fertilizers - agricultural burning
what are the natural co2 sources
- plant respiration - microbial respiration and decomposition - air-sea gas exchange
what are the major anthropogenic sources of tropospheric ch4
- rice cultivation - animal farming - agricultural burning - natural gas mining and transportation
what is the physical basis for the above ratio determination
- water molecules with the heavier isotopes 18O or 2H evaporate at a HIGHER temp than those with lighter isotopes - we can see that there is warmer climate by incr in heavier isotopes in frozen precipitation (ice sheets)
what atm aerosols scatter the incoming solar radiation
- wind-blown dust - fly ash - nitrate - sulfate
what is the average global monthly surface daytime temp range on the earth
-25 to 45 celsius
what 3 energy sources have the lowest co2 emissions during their lifecycle?
1. nuclear power 2. hydroelectric 3. wind
what are the 2 factors contributing most to the uncertainty in determining climate forcing
1. short term aerosol 2. cloud forcing values
what are the 5 different climate groups on earth?
1. tropical 2. dry 3. temperate 4. continental 5. polar
how much have ch4 levels increased in the atm since 1750?
1.16 ppm
how much have co2 levels increased in the atm since 1750?
130ppm A LOT
what was the mean annual surface temp of the earth in 2010
14.86 celsius
how do the stable isotopic ratios change if the ocean temperature decreases
18/16 and 2/1 will DECREASE
what stable isotpic ratio is used to determine the past ocean temp from ocean sedimentation cores
18O/16O
what 2 stable isotopic ratios were used to determine the variation in mean ocean temperatures over time as determined from their measurements in ice cores
18O/16O and 2H/1H
in what year was it determined that the atm level of co2 was 310 ppm
1950
how far back before the present can ocean sediment data be used
200 000 million years
what was the maximum CO2 concentration during the past 400 000 years
300 ppm
what was the level of co2 in 2018
410 ppm
what is the latest assessment report from the ipcc called
AR5
what re the next 3 strongest gases imp in climate change (after water)
CO2, CH4, N2O
what are the greenhouse gases in the atmosphere
H2O, CO2, CH4, N2O, tropospheric O3, CFCs, HCFCs
what are the 4 representative concentration pathways used in GCM models to predict climate change by 2100
RCP2.6, RCP4.5, RCP6, RCP8.5
what is the major source of ch4
anaerobic bacteria
what is the major source of n2o
anaerobic bacterial decomposition of organic materials in wetlands
what species cause negative climate forcing
backscattering of incoming radiation by clouds which results in atm cooling
what components of atm aerosols are the strongest absorbers of incoming solar radiation
black carbon and organic carbon
how is it removed from the troposphere
condensation to form clouds followed by precipitation (naturally)
what is climate forcing
considering all of the influences that change the amount of energy absorbed or lost which cause temps to rise or fall
what kind of climate forcing does absorption by black carbon and organic carbon in aerosols cause
positive climate forcing
how is current climate change different from past climate change without man's influence with regard to time scales
global climate change is occurring on a SHORTER TIME SCALE than in the past which occurred gradually over thousands of years
what is the major cause of the temp changes
increase in green house gases -- ESPECIALLY CO2
what is the IPCC
intergovernmental panel on climate change
how does 2010 differ from the 20th century regarding surface temp
it is .96 celsius above what it was in the 20th century
the waxy organic substances that are buried in the sediments gradually form an insoluble organic material called what?
kerogen
what part of the sediment core is used to measure the isotope ratios
macroscopic and microscopic shells found in the sediments
according the the AR5 what would be the outcome if anthropogenic co2 emissions were stopped today
many of the surface temp changes and impacts on terrestrial systems will continue due to the increased overburden of co2 relative to pre 1850 levels
what are the type of organic materials that are deposited in the following environments: marine, terrestrial, lacustrine
marine: phytoplankton and zooplankton terrestrial: plants lacustrine: algae
what is the major sink for n2o
mixing into the stratosphere
what kind of climate forcing does scattering of incoming solar radiation cause
negative climate forcing
what are the concentration pathways named for
possible changes in radiative forcing in Wm^-2 by the year 2100
how do weather and climate differ
weather is the state of the atmosphere at a particular place and time while climate is the average of weather over a long period of time
the complete combustion of fuel requires what reactant to be in excess
oxygen
what are the natural sinks for co2
photosynthetic uptake and ocean uptake
how far back before the present can ice core data be used to determine temp changes
present back in time to about 800 000 years
what is the most important sink for ch4
reaction with OH radical
one what basis are the 5 climate groups subdivided
seasonal precipitation types and level of heat
what is the range of temp and mean sea-level rise predicted by the late 21st century in all RCPs
temo: incr .3-4.9 celsius seal level: incr .17 to .82 m
what is climate
the average condition of the weather at a given region over a long period of time as exhibited by temperature, wind velocity, and precipitation
what is the strongest greenhouse gas
water vapor
