Volcanoes Pt. III + IV

Question 1

what chemical that has greatest impacts on climate on shorter time-scales?

Answer 1

sulphur

Question 2

where do very large eruptions (duration of eruption also matters) inject aerosols and ash?

Answer 2

-stratosphere (no weather to remove material unlike trophospere)

Question 3

sulfur that enter the stratosphere does what?

Answer 3

reacts with water and form H2SO4 droplets which are highly reflective and scatter and absorb incoming solar radiation so troposphere cools but stratopshere warms

Question 4

increases in optical depth after volcano eruption indicated what?

Answer 4

global atmospheric circulation of aerosols so eruption in the tropics are more likely to have global impacts on climate

Question 5

the different variables that affect impact eruption makes on climate

Answer 5

-time of year
-location
-weather patterns
-volatile content
-eruption style/length

Question 6

Volcanic Explosivity Index (VEI) is a scale that describes what?

Answer 6

the size of explosive volcanic eruptions based on magnitude and intensity

Question 7

basaltic eruptions are often are much more sulfur-rich than ____ ones so can have major effects even if they aren’t as explosive

Answer 7

felsic

Question 8

multiple closely spaced eruptions could cause what climate effect?

Answer 8

-more persistent climate perturbation because cooling may be extended (climate feedbacks)

Question 9

LIPS stands for what?

Answer 9

large igneous provinces (aka continental flood basalts)

Question 10

LIPS represent times when large volumes of mostly ___ magmas were generated/extruded onto landscape. where do they form?

Answer 10

-mafic magmas
-form independent of plate setting (in oceans, continents, within plates or between them; at hot spots/mantle plumes)

Question 11

short term climate effects

Answer 11

cooling (ozone depletion, acid rain, cooling)

Question 12

long term climate effects

Answer 12

global warming (CO2)

Question 13

climatic issues beyond cooling/warming from LIPS

Answer 13

-ocean acidification
-ocean anoxia
-acid rain
-gas and impacts block light - photosynthetic shutdown

Question 14

LIPS of mass extinctions

Answer 14

1)devonian: Viluy LIPS
2)Permian: Siberian Traps LIPS
3)Triassic: CAMP LIP
4) creat:Deccan Traps LIP
(maybe Ordovician)

Question 15

LIPS can explain many of the distinctive features commonly seen in the geologic records of most major extinctions:

Answer 15

• Loss of carbonate deposition in oceans (re: acidification)
• Negative carbon isotopic excursions (thermogenic greenhouse gases?) and
  persistent instability
• Spikes in metal deposition
• Other isotopic excursions (i.e., sulfur, mercury, nitrogen)

Question 16

Long term carbon cycling: silicate-carbonate weathering cycle

Answer 16

carbonate–silicate geochemical cycle, also known as the inorganic carbon cycle, describes the long-term transformation of silicate rocks to carbonate rocks by weathering and sedimentation, and the transformation of carbonate rocks back into silicate rocks by metamorphism and volcanism.

Question 17

what is glacial pump? (reverse now -> volcanism caused by climate change)

Answer 17

volcanism increases in response to deglaciation and isostatic rebound

Question 18

volcanoes don’t produce smoke bu ____

Answer 18

ash

Question 19

detailed mapping of ____ is key to determing eruption freq & magnitude (determines VEI). produces which type of map?

Answer 19

tephra
isopach maps (establishing eruption histories)

Question 20

signs that magma is moving but at deep depths

Answer 20

-elevated CO2 emissions
-deep long period earthquale
-aseismic inflation
-changes in water chmistry and thermal output

Question 21

signs that magma is moving but at shallow depths

Answer 21

-ground deformation
-Volcano-tectonic seismicity
-ground cracking/glacial melting
-sulfur degassing
-H2S to SO2 change emssions
-phreatic explosions

Question 22

canada doesn’t have what?

Answer 22

volcanic monitoring programs despite being volcanic country

Question 23

monitoring equipment includes what?

Answer 23

seismometers, tiltmers, GPS, gas monitoring stations, airborne surveys, remote sensing from space/aircraft

Question 24

can we predict eruptions

Answer 24

swarms indicate moving magma

Question 25

response to volcanoes

Answer 25

1) escape routes
2) early warming systems (sirens)
3) downloadable maps