# Presentation: 247797

## MODIS Level 3:  

- Future Issues and Considerations
- Brent Maddux

- 2001-2004 Cloud Fraction Mean

- 1

- 0.5

- 0

## How do the MODIS L3 products look:

-  Do they represent known physical phenomenon well?

-  What is L3 saying?
-  Some limitations of  L3 SDSs
-  How do we interpret the data effectively?

-  decrease the limitations
-  improve physical meaning and interpretation

- Going from information to knowledge:

- Next steps:

## DJF High Cloud

-  DJF All Cloud

- HIRS

- HIRS

- Aqua

- Terra

- Terra

- Aqua

- 1.0

- 0.8

- 0.6

- 0.4

- 0.2

- 0.0

## Cloud Top Pressure May 1st, 2003

- Dust or high aerosol events

- 200 	      400                 600                 800             1000

- mb

- Cloud Top Pressure May 1st, 2003

-  Events last several days

-  Few if any visible clouds

-  750-900 mb

-  For daily data this can be accounted for, but not weekly or monthly.

## Aqua

-  0                200            400             600            800

- Terra

- Difference

- -800          -400               0              400            800

- Cloud Ice Water Path December 2002

- Major ice cloud events?

- g/m^2

- g/m^2

## Difference

-    0   	    	    150                            300

- Cloud Liquid Water Path December 2002

- Aqua

- Terra

- g/m^2

- g/m^2

-     -150   	    	       0                               150

- Major liquid cloud events?

## Possible Solutions:

-   0                     15                      30

- Ocean Mass Concentration

-  Conduct secondary data processing
-  Remove questionable data
-  Create uncertainty products

- 0	            500                1000

- Cloud Top Pressure

- 1x10^-6 g/m^2

- mb

## Ice Particle Size and Tropical Deep Convection Evolution

- 0               15                30               45              60

- μm

- 0              200              400              600           800

- 0              250              500             750          1000

- g/m^2

- mb

- -Uniform re ice over cores

- -Isolated deep convection

- -Evident cirrus shields

-  Ice particle size increase away from deep convection

- Ice Particle Radius

- Ice Water     Path

- Cloud Top Pressure

-  What would scatter plots show?

## Mean SDS Comparisons

-  Mean phase properties can’t be fully characterized

##  Mean Ice Properties:

- 0        15        30        45        60

- 0        15        30        45        60

- Ice Effective Radius  (μm)

- Cloud Top Pressure  (mb)

- Ice Effective Radius  (μm)

- Water Path of Ice  (g/m^2)

- 0             1000           2000

- 0            500             1000

- IWP vs Re Ice

- CTP vs Re Ice

-  cloud regimes
-  cloud height or phase
-  particle size or path

- Ambiguous

-   Property comparison limitations:
-  data subsets (large particle size,  phase, etc)
-  multiple data set comparison

-   Possible solutions:
-  new joint histogram (in collection 5)
-  means of property subsets
-  multi dimensional histograms

-  Mean Ice Properties:

## Summary and Conclusions:

-  Implement a secondary processing between L2 and L3.
-  Add additional SDSs
-         1) that can be used to further compare the microphysical              	  properties of clouds and other atmospheric parameters
-         2) that allow for a further intuitive interpretations
-         3) near nadir.

## Image courtesy of MODIS Rapid Response Project at NASA/GSFC 

- Image courtesy of MODIS Rapid Response Project at NASA/GSFC

## Slide 13

## Slide 14

## Slide 15

## Slide 16

## Nov 2001

## October 2002

## Slide 19