Climate Indices
Climate indices are simple diagnostic quantities that are used to characterize an aspect of a geophysical system such as a circulation pattern. They track droughts, ENSO events, wind patterns, internal modes of climate variability, and extreme events like wildfires and heatwaves. Climate indices play a key role in climate monitoring and prediction. The climate index overview page summarizes the philosophy of climate indices.
To find a specific climate index, jump to the search box below or click your desired index from among the blue sub-category buttons.
To see only the indices with in-depth commentary, select the "Datasets with guidance" button when using the search box.
Dataset Overviews
Climate datasets
![Atlantic Multi-decadal Oscillation (AMO) Atlantic Multi-decadal Oscillation (AMO)](/sites/default/files/styles/medium/public/2022-03/AMOindex-Zhang.png?itok=A0P62TAr)
Years of record
- to
The Atlantic Multi-decadal Oscillation (AMO) has been identified as a coherent mode of natural variability occurring in the North Atlantic Ocean with an estimated period of…
-
Timestep
- Monthly, Decadal
-
Collections
- Climate Analysis Section (CAS) Data Catalog
Experts contributing reviews
- Trenberth, Kevin | Zhang, Rong
![Standardized Precipitation Evapotranspiration Index (SPEI) Standardized Precipitation Evapotranspiration Index (SPEI)](/sites/default/files/styles/medium/public/2022-03/SPEI.png?itok=64dJ85gE)
Years of record
- to
The Standardized Precipitation Evapotranspiration Index (SPEI) is an extension of the widely used Standardized Precipitation Index (SPI). The SPEI is designed to take into…
Main variables and Earth System components
N/AExperts contributing reviews
- Vicente-Serrano, Sergio M.
![NSIDC Sea Ice Index NSIDC Sea Ice Index](/sites/default/files/styles/medium/public/2022-03/NSIDC-Sea-Ice-Index.png?itok=Yq926eQX)
Years of record
- to
The NSIDC Sea Ice Index is a suite of easy-to-use sea ice analyses to track changes in Arctic and Antarctic sea ice. The product is produced and supported by the NOAA at…
Experts contributing reviews
- Meier, Walter
![Pacific Decadal Oscillation (PDO): Definition and Indices Pacific Decadal Oscillation (PDO): Definition and Indices](/sites/default/files/styles/medium/public/2022-03/PDO-pattern.png?itok=tGsYIU7B)
Years of record
- to
The Pacific Decadal Oscillation (PDO) is defined by the leading pattern (EOF) of sea surface temperature (SST) anomalies in the North Pacific basin (typically, polewards of…
-
Formats
- ascii
-
Timestep
- Monthly
-
Domain
- Pacific Ocean
-
Collections
- N/A
Experts contributing reviews
- Deser, Clara | Trenberth, Kevin
![Palmer Drought Severity Index (PDSI) Palmer Drought Severity Index (PDSI)](/sites/default/files/styles/medium/public/2022-03/palmer_0.gif?itok=tk8OkLjH)
Years of record
- N/A
The Palmer Drought Severity Index (PDSI) uses readily available temperature and precipitation data to estimate relative dryness. It is a standardized index that generally…
-
Timestep
- Monthly
-
Domain
- Global
-
Collections
- Climate Analysis Section (CAS) Data Catalog
Experts contributing reviews
- Dai, Aiguo
![FWI p95 in ERAI and CESM1-LE (contributed by Danielle Touma)](/sites/default/files/styles/medium/public/2023-08/Touma-FW_-Fig2.png?itok=d6KLSghy)
Years of record
- N/A
Fire weather indices are used to quantify the meteorological conditions that can lead to fire ignition and spread. They are used to communicate fire danger levels to…
Main variables and Earth System components
Atmosphere-
Formats
- N/A
-
Timestep
- N/A
-
Domain
- N/A
-
Collections
- N/A
Experts contributing reviews
- Touma, Danielle
![Drought atlases from tree rings Drought atlases from tree rings](/sites/default/files/styles/medium/public/2022-03/drought-atlases.png?itok=Jg903iiq)
Years of record
- to
Tree-ring drought atlases provide a paleoclimate analog to modern drought indices, most commonly the Palmer Drought Severity Index (PDSI). Produced on a regular lat-…
-
Timestep
- Annual
-
Domain
- North America
-
Collections
- N/A
Experts contributing reviews
- Cook, Edward
![U.S. Climate Extremes Index (CEI) U.S. Climate Extremes Index (CEI)](/sites/default/files/styles/medium/public/2022-03/US-climate-extremes-index.png?itok=Mm5-1eoR)
Years of record
- to
The U.S. Climate Extremes Index (CEI) was first presented in 1995 as a framework for quantifying observed changes in climate within the contiguous United States. At…
Main variables and Earth System components
Atmosphere Air Temperature Maximum Air Temperature Minimum Air Temperature Precipitation Wind Land Drought-
Formats
- ascii
-
Timestep
- Monthly, Seasonal, Annual
-
Domain
- North America
-
Collections
- N/A
Experts contributing reviews
- Gleason, Karin
![NOAA ThreadEx Long-term Station Extremes for America NOAA ThreadEx Long-term Station Extremes for America](/sites/default/files/styles/medium/public/2022-03/teaser_images_616.png?itok=XA0TT96n)
Years of record
- to
ThreadEx is a data set of extreme daily temperature and precipitation values for 270 locations in the United States. For each day of the year at each station, ThreadEx…
Main variables and Earth System components
Atmosphere Air Temperature Maximum Air Temperature Minimum Air Temperature Precipitation-
Formats
- ascii
-
Timestep
- Daily
-
Domain
- North America
-
Collections
- N/A
Experts contributing reviews
- N/A
![Asymmetry and Diversity in the pattern, amplitude and duration of El Niño and La Niña Asymmetry and Diversity in the pattern, amplitude and duration of El Niño and La Niña](/sites/default/files/styles/medium/public/2022-03/Santoso-snippet.png?itok=FFNoG7X6)
Years of record
- N/A
El Niño and La Niña, the two phases of ENSO, are sometimes described as opposites. However, there are asymmetries in their spatial structure, amplitude, duration and…
-
Formats
- N/A
-
Timestep
- N/A
-
Domain
- Tropics
-
Collections
- N/A
Experts contributing reviews
- Santoso, Agus
![Meridional Modes and their indices Meridional Modes and their indices](/sites/default/files/styles/medium/public/2022-03/NPMM_schematic.png?itok=_YAO699f)
Years of record
- N/A
In each of the world’s tropical ocean basins, year-to-year climate variability is primarily governed by fluctuations in the zonal sea surface temperature (SST) gradient and…
-
Formats
- N/A
-
Timestep
- N/A
-
Domain
- Atlantic Ocean, Pacific Ocean
-
Collections
- N/A
Experts contributing reviews
- Amaya, Dillon