Transcript Cenozoic Model- LAST GROUPx

Modeling the Cenozoic
Icehouse Earth
ERTH 500
Mayra Dudrenova
Symone Hopkins
Adam Rincon
Rock Module
Original Model
● In-class Himalayan Rock Mass Module
● Assumed a lot of simplifications
● Difficulties constructing the model
a)Finding relationships
between erosion and other
the converters.
the
b)Using the given equations
to type in relationships
c) Trouble with the complexity of
relationships
d)Understand Stella and its
various components
Rock Module
Complete Model
-Model obtained from class folder
-More complex and interconnected
Default Model Configuration
•Run Specs
–Model runs for 60 million years
–Time step is 5,000 years
–Takes 1 minute, 45 seconds to run on 2015 MacBook Pro laptop
•Tectonic Forcing
–No collision for 10 million years (10 Myrs)
•Allows model to approach equilibrium
in pre-collision environment
–India collides with Asia 50 Myrs ago
•Initial rate = 3 cm/year
•Declines steadily to 1.5 cm/year over next 10 Myrs
•Stays steady at 1.5 cm/year for last 40 Myrs
–Sea-floor spreading (and so volcanic outgassing) stays constant the whole time
Default Model Configuration (cont’d)
•Atmospheric Carbon and Surface Temperature
–Initial mass of atmospheric carbon = 1068 Gtons
•Approximately model’s steady-state value, pre-collision
•Perhaps 60% of actual amount 50 Myrs ago?
•Pre-collision weathering rate too high?
– Initial temperature: 289.5 K (26.4°C)
•Much colder (9 - 10°C?) than Earth 50 Myrs ago
•Reflects under-calculation of atmospheric carbon
Model Graph using given values for Indian Crust Speed
Model Graph after decreasing Indian Crust Speed by a factor of 10
Model Graph after decreasing Indian Crust Speed by a factor of 10
Results of the Experiment
Mountain Height decreased from 6800 meters to 680 meters.
Erosion rate decreased by power of 10
Tectonic Convergence decreased by power of 10
Atmospheric Carbon increased from 752 Gtons to 1061 Gtons
Silicate Weathering Mts decreased from 11608 Gtons to 240 Gtons
Silicate Weathering Global increased from 58392(Gt/Myr) to 69760 (Gt/Myr)?
Tsfc increased from 288(K) to 289(K)
Mtn Precipitation Rate decreased from 2.5 m/yr to 0.92m/yr
Carbon module in the Himalayas
By
Mayra Dudrenova
My original Carbon model
It has 3 reservoirs with 2 flows going from
atmospheric carbon mass to carbon
mass in the ocean.
The first flow is for weathering of the
Himalayas and the second flow for the
global weathering rate.
Riddled with errors, and missing values (as
seen by the ?)
Second phase
This model ran, but the carbon
would go to zero if you tried to run
it to a million years and with a
faster running speck of DT: 2.
We wanted to go all the way to 50
million years, so this wouldn’t do.
Long Term Inorganic Carbon Budget: Atmospheric Carbon,
Weathering, and Global mean Surface temperature and
Precipitation
Simulation: Default Configuration
Atmospheric Carbon, Weathering, and
Global Mean Surface Temp
Results of experiment
Increased the CWRMtnRef
From 7.0e4 to 7.0e14.
Model would not run because it
said that it had to divide by zero or
the value is too high for the DT to
handle.
Results of experiment
Purple line: Carbon mass in
atmosphere decreased to
752 Gt
Green line 1: Temperature
decreased by 2 degree K.
Orange line: global SWR
started at 70,000 and
decreased to ~58,000.
Green line 4: Mtn SWR started
at 0 and increased to
12,000.
Precipitation module in the
Himalayas
by
Symone Hopkins
The Precipitation Component
configure a precipitation rate based on
Contemporary rates over the himalayas
Rates over flat land
Determine Linear relationship between precipitation rate and mountain
height
*completely components, there are no reservoirs or sources/sinks
Importance to System
Higher Precipitation→ higher erosion
More Co2→ warmer planet→ potential to hold more water→ more precipitation
Needed for modleing
Mountain dimensions ie height, length, etc.
General Equation
Rate of water mass = the change in mixing ratio x (mountain length x height of slope) x flux of air mass through unit of
surface area at mountain base
Assumptions:
Temperature at base of mountain
Air pressure at mountain base
Found quantities:
Water vapor pressure
Air density at bottom of mountain
Temperature at the top of the mountain
Wind upslope speed
My Model
My graph
Unable to run my graph due to an unidentified issue within my model most likely
an equation written incorrectly.
Modeling comments
. straight forward as a program
.difficult to find errors when you get an unexpected result
.syntax is important
.difficult to find upslope wind velocity
Himalayan Precipitation Rate
Simulation: Default Configuration
Himalayan Precipitation Rate
Differences
My equation sheet
Given equation sheet
What happens when average precipitation rate is changed?
20% increase