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6 votes
Accepted

Reducing image collection to get daily sum from hourly precipitation and extraction of polygon data?

This post explains how to do that for months. Here it is adapted for days: var gsmap = ee.ImageCollection('JAXA/GPM_L3/GSMaP/v6/operational') .select(['hourlyPrecipRate']) .filterDate('2015-...
Nicholas Clinton's user avatar
4 votes

Locate wet patches using DEM

The subject has a lot of atention among specialists and the number of tools available depends on the amount of work you wnat to put on it. The paradox is that you want to avoid wet areas while ...
Marco's user avatar
  • 3,240
4 votes
Accepted

Storm Total Precip Map

Your NoData cells actually contain the value -10'000 and therefore produce said "strange values". So you need to tell the Raster Calculator to ignore these values. You can do this using SetNull (see ...
dru87's user avatar
  • 1,477
4 votes
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Download GLDAS precipitation monthly 1 km resolution data by Earth-engine

For GLDAS precipitation monthly you could use 'Rainf_f_tavg' or 'Rainf_tavg' bands from 3 hourly "NASA/GLDAS/V20/NOAH/G025/T3H" product (resolution of 0.25 arc degrees). It would produce 8 daily ...
xunilk's user avatar
  • 30k
4 votes

Google Earth Engine: precipitation data, summing monthly data is not matching annual sum

As your code has several issues, I fixed them for adequately running it. On the other hand, as your HUC6_RMP bound is unknown for me, I assumed an arbitrary point in Idaho for only two years (1994, ...
xunilk's user avatar
  • 30k
3 votes

Bilinear resampling yields inaccurate/small values (Earth Engine)

This question is over 2 years old, but I was having the same issue and worked out what was going wrong, so here is my answer. The problem is in how Google Earth Engine handles projections. The help ...
G-Lomax's user avatar
  • 80
3 votes
Accepted

GEE Converting Units of the FLDAS Precipitation data (Rainf_f_tavg) from kg m-2 s-1 to mm/month

You are trying to apply the .expression to the entire ImageCollection. Unfortunately .expression can only be applied to an ee.Image() object so you have to map your function over the entire image ...
Jobbo90's user avatar
  • 2,073
2 votes
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Daily temperature data portal globally

The Open Data Stack Exchange has an excellent community wiki question with links to many different sources of weather data: Sources of weather data
csk's user avatar
  • 24.9k
2 votes

Solving computing time problem when grid size element increases in flood model?

Depending on your problem and the nature of the details you want to keep, you might want to : Use a channel with cross sections in Flo-2D to have a close approach of the river bed Use coarser ...
Kantan's user avatar
  • 1,927
2 votes
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Batch raster operations to get Maximum Precipitation in Catchment

Here is a translation of the steps in your question to GRASS commands. Without knowing how your data are structured, I'll make some assumptions. Lets say the precipitation data are CSV files with ...
Micha's user avatar
  • 15.7k
2 votes

Locate wet patches using DEM

To fully answer your question I need more information on what exactly you define as "wet patches", but I believe that you are looking for the tool "Flow Accumulation", explained here by ESRI. You ...
Iridium's user avatar
  • 229
2 votes
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QGIS: Creating average of a precipitation multiple raster set?

If you want to take an average of all 12 images, the process is very simple. Within a raster calculator (this can be the calculator in the raster drop-down menu or the GDAL/GRASS/SAGA calculators in ...
Trevor J. Smith's user avatar
2 votes
Accepted

WGS84 projection is invalid for aggregations

In this section var precipNum = lastPrecip.reduceRegion(ee.Reducer.last(), geom) ... The issue is that lastPrecip is a temporary layer only stored in memory and doesn't have a nominal scale so GEE ...
Nishanta Khanal's user avatar
2 votes

Standardized Precipitation Index (SPI) equation using ArcGIS Desktop

Here you can find ArcGIS toolbox for calculating SPI. This toolbox was made with the same algorithm in the spreadsheet. https://github.com/Hyun-Woo-Jo/CalculateSPI/releases/tag/v1.0
Hyun Woo Jo's user avatar
2 votes

Interpreting GLDAS 2.1 precipitation data

The metadata says the following: "The GPCP 1-degree Daily (1DD) dataset is used and disaggregated to 3-hourly interval" From that, and since the timestamps in the filenames run from *0000* to *...
s6hebern's user avatar
  • 1,236
2 votes

Locate wet patches using DEM

Calculating the topographic wetness index should be of great use. Its a classic metric for determining likely wet and dry patches relative to the rest of the landscape based on the curvature and ...
Lovette's user avatar
  • 979
2 votes

How to find out which areas are affected by flooding due to heavy rain?

I am unsure how accurate you want your results to be, my understanding is that you can do one of two approaches: Find known water level points for the rainfall event and create an interpolated ...
MapInfoNewbie's user avatar
2 votes
Accepted

Selecting only CFSR images in Google Earth Engine with precipitation data

The hour is saved in the property forecast_hour of every Image. You can use this property and .filterMetadata() to filter only those with forecast_hour: 3. Here's the code: var dataset = ee....
JonasV's user avatar
  • 3,784
2 votes
Accepted

Iterating over dates to extract precipitation in Google Earth Engine

You do this by mapping over the feature collection. Unfortunately I think you didn't give access to your script to others, so I can't test it. But this should work: // CSV file var coord = ee....
JonasV's user avatar
  • 3,784
2 votes
Accepted

Contours into polygons with QGIS

Try extending the lines past the boundary of the polygon, like so:
Matt's user avatar
  • 17.6k
2 votes
Accepted

Raster values in R lacking decimals

Computers store integers more efficiently than floating point (decimal) numbers. To store a floating point as an integer without losing too much precision, you can add a fixed value (offset) and ...
Aaron Zuspan's user avatar
1 vote

Standardized Precipitation Index with gamma function

That is a limitation with GEE. More details and code are provided here in this regards: https://un-spider.org/advisory-support/recommended-practices/recommended-practice-drought-monitoring-spi/step-by-...
Shreyansh Vishwakarma's user avatar
1 vote
Accepted

Extract time-series rainfall from multiple point with date information

Your region POI is a single point. So you will never have more than a single pixel when you reduce that region. The mean() and sum() of a single pixel is the same, which is why the two charts are ...
Daniel Wiell's user avatar
  • 14.4k
1 vote

Rainfall interpolation using ArcMap

If your objective is just to smooth the colors, then no need to resample the data. You should only use resample during display feature in Display tab within Layer Properties window, and choose ...
user97103's user avatar
  • 537
1 vote
Accepted

Rainfall interpolation using ArcMap

Use the Resample tool and specify bilinear or cubic as the resampling type.
user2856's user avatar
  • 67.2k
1 vote

Standardized Precipitation Index (SPI) equation using ArcGIS Desktop

There was a discussion at GeoNet titled How to calculate Standard Precipitation Index (SPI) using ArcGIS which suggests that there is a way to "calculate the SPI using monthly CHIRPS CHG - Data" using ...
PolyGeo's user avatar
  • 65.2k
1 vote

Clustering Raster Monthly Precipitation Pattern

After I posted my other answer, I realized there's a much faster way to do it. Use the Raster Pixels to points tool on one of your rasters. This creates a point layer with one point per pixel. Use ...
csk's user avatar
  • 24.9k
1 vote

TRMM 3B42RT product has no Coordinate Reference System?

Let's look first at the information provided by gadlinfo for the 3B42RT.2016010100.7.7day.tif file: C:\>gdalinfo 3B42RT.2016010100.7.7day.tif Driver: GTiff/GeoTIFF Files: 3B42RT.2016010100.7....
Gabriel De Luca's user avatar
1 vote

Moisture Stress Index - how important is seasonal influence in a deciduous forest?

The seasons have a significant impact on the biochemistry and biomechanics of deciduous tree species. What you are experiencing is not necessarily surprising because when a deciduous species undergoes ...
AWGIS's user avatar
  • 3,230
1 vote

Summation of multiple map layers?

To do this by year, you can reduce the timeframe of each individual year using ee.Reducer.sum() and then add the two years together: var dataset = ee.ImageCollection('IDAHO_EPSCOR/GRIDMET'); var ...
JepsonNomad's user avatar
  • 2,166

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