Rawlins Academy– Val Cenis 2017. Val Cenis Val Cenis by Night.
Maria Val Martin and J. Logan (Harvard Univ., USA)
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Transcript of Maria Val Martin and J. Logan (Harvard Univ., USA)
Maria Val Martin and J. Logan (Harvard Univ., USA)
D. Nelson, C. Ichoku, R. Kahn and D. Diner (NASA, USA)
S. Freitas (INPE, Brazil)
F.-Y. Leung (Washington State Univ., USA)
Research funded by NSF and EPA
Wildfire Plume Injection Heights Over North America: An Analysis
of MISR, MODIS and a 1-D Plume-rise Model
Outline An statistical analysis of aerosol injection heights
over North America The use of a 1-D plume-rise model to develop a
parameterization of the injection heights of North American wildfire emissions
Wildfire Plume Injection Heights Over North America: An Analysis
of MISR, MODIS and a 1-D Plume-rise Model
Multi-angle Imaging SpectroRadiometer- MISR
9 view angles at Earth surface: nadir to 70.5º forward and backward
4 bands at each angle:446, 558, 672, 866 nm
Continuous pole-to-pole coverage on orbit dayside
400-km swath9 day coverage at equator2 day coverage at poles
Overpass around local noon time in high and mid- latitudes
275 m - 1.1 km sampling
In polar orbit aboard Terra since December 1999
MISR Plumes: MISR INteractive eXplorer (MINX)
http://www.openchannelsoftware.org
Smoke plume over central Alaska on June 2002
Cross-section of heights as a function of distance from the source
Histogram of heights retrieved by MINX
About 3500 plumes digitalized over North America
20022004200520062007
http://www-misr2.jpl.nasa.gov/EPA-Plumes/
Plume Distribution, Atmospheric Conditions and Fire Properties
pcR
dz
d/
PT where,Stability
P0
•Meteorological fields from
GEOS-4 and GEOS-5 2x2.5
•Fire Properties from MODIS Fire Radiative Power
Histogram of Plume Height Retrievals Atmospheric Stability Profile
Max
Avg Median
Mode
Plume Height?
Each individual height
Stable Layer
Boundary Layer (BL)
Leung et at, PosterB31C-0302
5-30% smoke emissions are injected above the boundary
layer
Kahn et al, [2008]
Distribution of MISR heights-PBL for smoke plumes
2004
200210–25%
20054–15%
20069–28%
20079–18%
Val Martin et al, in preparation
Tropical Forest
Cropland
Temperate Forest
Boreal Forest
Boreal Shrub
Non-Boreal Shrub
Boreal Grassland
Non-Boreal Grassland
Vegetation type based on MODIS IGBP land cover map
(http://modis-land.gsfc.nasa.gov/landcover.htm)
1x1 kmresolution
Classification of plume distribution by vegetation type
Percentage of smoke above BL varies with vegetation type and fire season
2002
2004200520062007
% Height retrievals with [Height-PBL] > 0.5 km
Number of plumes
Close relationship between plume distribution, fire intensity and fire size
Plume Height versus Fire Intensity
Plume Height versus Fire Size
Fire intensity drives the interannual variability of plume heights
20022004200520062007
Distribution of MISR heights and MODIS FRP by year
200
200
Also, fire intensity drives the seasonality of plume heights
Boreal Forest2002 and 2004-2007
1-D Plume-resolving Model
Detailed information in Freitas et al, [2007]
Key input parameters:•Instant fire size: MODIS FRP (max FRP observed in each biome 1 km2 burned [Charles Ichoku, personal communication])
•Total heat flux: Max MODIS FRP observed over vegetation type x 10 [Wooster et al, 2005; Freeborn et al., 2008]
•RH, T, P, wind speed and direction: from GEOS-4 meteo fields 2x2.5
• Fuel moisture content: from the Canadian Fire Weather Model
Simulation of a boreal fire plume in Alaska and a grassland fire plume in Mexico
Fire Size= 300 HaHeat Flux= 18 kW/m2
Fire Size= 3.3 HaHeat Flux= 9 kW/m2
MISR Retrieved HeightsMISR Smoke Plume 1D Plume-rise Model
Boreal Forest Fire
Grassland Fire
Simulation of a boreal fire plume in Alaska and a grassland fire plume in Mexico
Fire Size= 300 HaHeat Flux= 18 kW/m2
Fire Size= 3.3 HaHeat Flux= 9 kW/m2
MISR Retrieved HeightsMISR Smoke Plume 1D Plume-rise Model
Boreal Forest Fire
Grassland Fire
5025 m 5425 m
1200 m
900 m
The 1-D Plume-resolving Model simulates fairly well the observed MISR heights
Correlation between simulated plume heights and MISR observed heights over North America
2688N0.40r
25.0Int1.84) -(0.73 1.15slope
2
All Plumes
5-30% of smoke emissions are injected above the BL.
The percentage of smoke that reaches the FT depends on fire characteristics (e.g., vegetation type, fire intensity, etc) and year-to-year variations .
Fire intensity drives the seasonality and interannual variability of the plume heights.
1-D plume-resolving model simulates fairly well the observed MISR plume heights.
In the future, we plan to embed the 1-D plume-resolving model with GEOS-Chem to simulate vertical transport of North American wildfire emissions.
Concluding Remarks
Extra Slides
The 1-D Plume-resolving Model simulates fairly well the observed MISR heights
Correlation between simulated plume heights and MISR observed heights over North America
677N0.31r
43.0Int1.91) -(0.59 1.06slope
2
Boreal Forest Plumes
The 1-D Plume-resolving Model simulates fairly well the observed MISR heights
Correlation between simulated plume heights and MISR observed heights over North America
309N0.53r
06.0Int1.75) -(0.93 1.28slope
2
Temperate Forest Plumes
Model simulated heights versus MISR observed heights by year
Model simulated heights versus MISR observed heights by vegetation
Smoke emissions tend to get confined within stable layers in the atmosphere, when they
exist
11% 13% 7% 24%13%
Distribution of all individual heights in the FT – Stable Layer
MISR Height – Stable Layer Height ≈ 0 km
Relationship between simulated heights and 1-D model input parameters
The 1D plume-resolving model: Governing equations
dynamics
thermodynamics
water vapor conservation
bulk microphysics
cloud water conservation
rain/ice conservation
The 1D plume-resolving model: The lower boundary conditions
Intensity of the fire drives the interannual variability of plume heights
Also, fire intensity drives the seasonality of plume heights
Trop Forest
Also, fire intensity drives the seasonality of plume heights
Temperate Forest
Also, fire intensity drives the seasonality of plume heights
Boreal Shrub
Also, fire intensity drives the seasonality of plume heights
Boreal Grassland
Also, fire intensity drives the seasonality of plume heights
NonBoreal Grassland
Also, fire intensity drives the seasonality of plume heights
Cropland