The Earth Trends Modeler (ETM) is an integrated suite of tools within IDRISI for the analysis of image time series data associated with Earth Observation remotely sensed imagery. With ETM, users can rapidly assess long term climate trends, measure seasonal trends in phenology, and decompose image time series to seek recurrent patterns in space and time.

EOT El Nino Climate Change Analysis X1 s

An Empirical Orthogonal Teleconnection (EOT) analysis of monthly anomalies in sea surface temperature (SST) from 1982 to 2007.

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With ETM, users can address such questions as:  

  • “How have temperatures changed over the past 30 years?”
  • “Are plants exhibiting a later senescence?”
  • “Are there recurrent spatial patterns in phytoplankton productivity?”
  • “What are the geographic impacts of climate events such as El Niño?”

No other software technology provides such a coordinated suite of data mining tools needed by the earth system science community for climate change analysis and impact assessment.

Tools in ETM include:

  • Parametric and non-parametric trend measures
  • Seasonal trend analysis
  • Principal Components / Empirical Orthogonal Function analysis (PCA/EOF)
  • Extended PCA/EOF for the co-analysis of multiple series (EPCA/EEOF)
  • Multichannel Singular Spectrum Analysis (MSSA)
  • Empirical Orthogonal Teleconnection (EOT) analysis and extended modes
  • Canonical Correlation Analysis (CCA)
  • Lagged Linear Modeling
  • Fourier PCA and Wavelet analysis

While ETM is intended for professional use, its simple and intuitive interface makes it an excellent tool for teaching and self-exploration. The system includes a full tutorial and sample data sets.

Earth Trends Modeler Key Features

  • Extract and analyze long-term global trends and their impacts
  • Examine the relationship between time series
  • Examine trends in seasonality
  • Isolate true change from normal environmental variability
  • Uncover and analyze patterns of variability across temporal scales
  • Preprocess image time series data including noise removal and deseasoning

Earth Trends Modeler Detailed Specifications


Learn more about Earth Trends Modeler

IDRISI Spotlight: Earth Trends Modeler
Earth Trends Modeler Focus Paper
Climate Change Analysis
Time Series Analysis Video
IDRISI Selva Brochure
Geotemporal Analysis Video


Analytical Examples:

Explore Trends with Earth Trends Modeler in IDRISI Taiga GIS and Image Processing Software

An analysis of trends in sea surface temperature from 1982 to 2006. The strong monotonic trend of increasing temperature in the Atlantic is seen to be related to the Atlantic Multidecadal Oscillation (AMO) as determined from a temporal regression with four major climate teleconnection indices.

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An illustration of several trend measures. The top image measures linearity in trends in sea surface temperature. As can be seen, the most linear trends include increases in the East and West Greenland currents and the Labrador Sea (all parts of the North Atlantic Subpolar Gyre), and the region at the mouth of the Amazon, most particularly, the Orinoco River.

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Clark University