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Rainfall Distribution Mapping

Definition

Rainfall distribution mapping depicts spatial patterns of precipitation using gauge networks, weather radar, satellites, and model analyses. Techniques include interpolation (kriging, IDW), radar–gauge merging, and bias correction for terrain effects. Time windows range from storm events to climatological normals. Maps inform flood modeling, agriculture, water-resource planning, and climate assessments. Uncertainty is managed by publishing coverage masks, error statistics, and differences between sensors. Because radar beams overshoot distant low-level rain and satellites struggle near coasts or mountains, blended products often perform best. Clear legends, units (mm/inches), and time stamps prevent misinterpretation.

Application

Flood analysts derive design storms; farmers plan irrigation; cities size drainage; hydrologists calibrate models; climate scientists examine trends. Emergency managers track storm footprints for damage assessment.

FAQ

What sensor combination works best?

Gauge-corrected radar for events; satellite + reanalysis for data-sparse regions; always validate locally if possible.

How to avoid contour artifacts?

Choose appropriate intervals and smoothing; show raw points and coverage gaps to temper overconfidence in poorly sampled areas.

Can we map extremes reliably?

Short-duration extremes are hard; use high-resolution radar and citizen-rain gauges, noting higher uncertainty.

How should time be represented?

Cumulative totals, intensities, and return-period classes; always include the start/end timestamps and time zone.