Fire Sync Data Analysis Christel’s Baby Steps to Temporal and Spatial Analyses
Overview Conceptual Map Study Design Data Charactistics Data Analysis Roadmap to Success Future Work
Conceptual Map CLIMATE ENSO, PDO, AMO Summer DROUGHT PDSI Winter ppt Summer soil moisture FIRE EVENTS Spatial/Temporal Dynamics -Year events -X, Y coord Fuel Oxygen, Ignition weather Forest Type, Landscape position, other
Study Design Observational Post Ex Facto Non-random Spatial Temporal
Data Characteristics Fire Site Categorical X,Y information Fire Event Time Series X,Y information Binary Data Clumping by climatic region could be count data Phase Events ENSO Event Time Series Binary Data? Other PDO, AMO Events as well? Phases Categories? PDSI Continuous index Grid Data Time series X,Y information
Data Characteristics Climate - normal Fire data ??Non-linear Correlated observations Inference? Ecological/Climatological Statistical Prediction? (Interpolation)
Conceptual Map CLIMATE ENSO, PDO, AMO Summer DROUGHT PDSI Winter ppt Summer soil moisture FIRE EVENTS Spatial/Temporal Dynamics -Year events -X, Y coord Fuel Oxygen, Ignition weather Forest Type, Landscape position, other
The Big Science Question El Nino Influence Yr Climate 1A, B, C 2A-, B, C 3A-, B, C- 4… Asynchronous spatial fire pattern over time??
Conceptual Map CLIMATE ENSO, PDO, AMO Summer DROUGHT PDSI Winter ppt Summer soil moisture FIRE EVENTS Spatial/Temporal Dynamics -Year events -X, Y coord Fuel Oxygen, Ignition weather Forest Type, Landscape position, other
Research Questions El Nino Influence Yr Climate 1A, B, C 2A-, B, C 3A-, B, C- 4… Does drought reflect climatic conditions – spatially and temporally?
Research Approach Superposed Epoch Analysis Nonparametric methods for correlated time series data Focuses to find signals around extreme events
Research Approach Superposed Epoch Analysis 77 sites related to drought in the year of the fire Temporal results Descriptive Mapping
Research Approach Spatial Relationships? Regionalize Analysis to deflat spatial influence Test for autocorrelation in distance (x,y)
Research Approach Regionalize Climatic – PDSI data PCA ordination
Research Approach Response Groups Fire Event data Clustering dendrograms Nonmetric multidimensional Scaling ordination
Sample Unit = Site
Sample Unit = Year
Research Approach Analyzing Spatial & Temporal at the same time?? “Synchrony” Definition: A process of adjustment of rhythms due to an interaction Spatial covariance in population density fluctuations
Synchrony Analysis Spatial covariance – Point Pattern Analysis Demonstrate scale Identify mechanisms Endogenous Exogenous Moran’s I Effect: density independent factor (e.g., climate) overrides local population regulators by large environmental shocks that synchonize the population
Synchrony Analysis Spatial Autocorrelation Pattern of nearby locations are more likely to have similar magnitude than by chance alone Signature of past spatial-temporal patterns
Synchrony Analysis Spatial Autocorrelation Coefficient Provide an average isotrophic estimation of autocorrelation at each distance class Formal testing with Confidence Intervals Bonferroni Adjustment Distances result in + or – relationships Displayed with correlograms
Synchrony Analysis Variogram Identify and model spatial pattern Predict (kriging) unmeasured areas value Require parameter fitting & model selection
Synchrony Analysis Variogram
Roadmap to success Hypothesis refinement Data statements & tests
Roadmap to success Exploratory data analysis All datasets Data format (binary, count, continuous…) Transformations? Outliers? Possible interaction terms (elevation, forest type)?
Roadmap to success Summary Analyses Multivariate/NMS (time or space) Clustering (time or space) Repeated measures SEA Variograms (scale)
Roadmap to success Statistical Inference & Prediction Model based methods
Future Work Spatio-temporal dynamics Fire, Drought, Climate oscillations Kurt – drought info Christel – fire info Grant - ENSO Comparison of dynamics Drought vs fire, etc. Prediction to unmeasured areas Hierarchal modelling