Remote Sensing,
Land Surface Modelling and Data Assimilation

Importance of Land Surface States
(soil moisture, soil temperature, snow)

Soil Moisture vs Sea Surface Temp

The Situation

The Problem With LSMs

Importance of Soil Moisture

Soil Moisture Coverage: Veg (Mean PR)

Soil Moisture Coverage: RFI (SD PR)

Data Assimilation Defined

Continuous or Sequential DA?

Continuous or Sequential DA?

Extended or Ensemble KF?

DA as a Spatial Interpolator

Case 1: 1D Synthetic Study

(Walker et al., AWR 2001)

Synthetic Data

Direct Insertion Every Hour

Kalman Filter Update Every Hour

Kalman Filter update Every 5 Days

Case 1: Lessons Learned

Case 2: 1D Field Study

(Walker et al., JHM 2001)

Field Instrumentation

Model Calibration/Evaluation

Kalman Filter Update Every 5 Days

Case 2: Lessons Learned

Case 3: 3D 6ha Field Study

(Walker et al., WRR In Review)

Modified Kalman Filter Application

Catchment Instrumentation

3D Model Calibration

3D Profile Retrieval

Case 3: Lessons Learned

Case 4: 1.5D Continental Synthetic Study
 
(Part 1: Demonstration)

(Walker and Houser, JGR 2001)

Catchment-based LSM

Catchment Discretisation

Synthetic Demonstration

“Errors” in Assimilated Moisture: 1

“Errors” in Assimilated Moisture: 2

Monthly Evapotranspiration

Monthly Runoff

Case 4.1: Lessons Learned

Case 4: 1.5D Continental Synthetic Study
 
(Part 2: Mission Requirements)

(Walker and Houser, WRR In Prep)

Motivation

Mission Requirements

Spatial Distribution of MC Error

Case 4.2: Lessons Learned

Case 4: 1.5D Continental
Synthetic Study
 
(Part 3: Extended v Ensemble KF)

(Reichle, Walker, Koster and Houser,
JHM Submitted)

Filter Calibration

Extended vs Ensemble KF

Case 4.3: Lessons Learned

Case 5: 1.5D Continental
“Field” Study

(Work in Progress)

Land Surface Initialisation for Seasonal-to-Interannual Prediction

Tier 1: Better Forcing

Tier 2: Assimilation

SMMR Soil Moisture Observations

Soil Moisture Time Series: Illinois

Animation

Soil Moisture: Lat 50, Lon -100

Evaluation of Assimilation

Final Words

Thankyou!