KBDI: Keetch-Byram Drought Index

AI-generated Key Takeaways

• The Keetch-Byram Drought Index (KBDI) is a continuous scale used for estimating soil and duff layer dryness.

• KBDI increases with dry days and temperature, and decreases with rain, reflecting meteorological drought.

• The scale ranges from 0 (no moisture deficit) to 800 (extreme drought) based on available soil moisture.

• KBDI is widely used globally for drought monitoring, wildfire prevention, and supporting rain-fed crops.

Dataset Availability

2007-01-01T00:00:00Z–2025-10-11T00:00:00Z

Dataset Provider

Institute of Industrial Science, The University of Tokyo, Japan

Earth Engine Snippet

ee.ImageCollection("UTOKYO/WTLAB/KBDI/v1")

Cadence

1 Day

Tags

drought fire rainfall

kbdi

lst-derived

utokyo

wtlab

Description

Keetch-Byram Drought Index (KBDI) is a continuous reference scale for estimating the dryness of the soil and duff layers. The index increases for each day without rain (the amount of increase depends on the daily high temperature) and decreases when it rains. This system is based primarily on recent rainfall patterns. It is a measure of meteorological drought; it reflects water gain or loss within the soil.

The scale ranges from 0 (no moisture deficit) to 800 (extreme drought). The range of the index is determined by assuming that there is 20 cm of moisture in a saturated soil that is readily available to the vegetation (Keetch and Byram, 1968). KBDI is world widely used for drought monitoring for national weather forecast, wildfire prevention and usefully especially in regions with rain-fed crops.

Bands

Pixel Size
4000 meters

Bands

Name	Min	Max	Pixel Size	Description
KBDI	0	800	meters	Keetch-Byram Drought Index

Terms of Use

Terms of Use

CC-BY-4.0

Citations

Citations:

• Wataru Takeuchi, Soni Darmawan, Rizatus Shofiyati, Mai Van Khiem, Kyaw San Oo, Uday Pimple and Suthy Heng, 2015. Near-real time meteorological drought monitoring and early warning system for croplands in Asia. 36th Asian conference on remote sensing (ACRS): Manila, Philippines, Oct. 20, 2015.

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Code Editor (JavaScript)

var collection = ee.ImageCollection('UTOKYO/WTLAB/KBDI/v1')
  .select('KBDI')
  .filterDate('2019-01-01', '2019-01-10');
var bandViz = {
  min: 0,
  max: 800,
  palette: [
    '001a4d', '003cb3', '80aaff', '336600', 'cccc00', 'cc9900', 'cc6600',
    '660033'
  ]
};
Map.addLayer(collection.mean(), bandViz, 'Keetch-Byram Drought Index');
Map.setCenter(120, 3, 3);

Open in Code Editor

KBDI: Keetch-Byram Drought Index

Keetch-Byram Drought Index (KBDI) is a continuous reference scale for estimating the dryness of the soil and duff layers. The index increases for each day without rain (the amount of increase depends on the daily high temperature) and decreases when it rains. This system is based primarily on recent rainfall …

UTOKYO/WTLAB/KBDI/v1, drought,fire,rainfall

2007-01-01T00:00:00Z/2025-10-11T00:00:00Z

-60 60 60 180

Google Earth Engine

https://developers.google.com/earth-engine/datasets