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Ecosystem Climate Regulation Services Calculator
http://www.ecosystemservicescalc.org
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Prepare new default data for all biome types #64

Closed teixeirak closed 8 years ago

teixeirak commented 9 years ago

Once we have selected a biomes map (issue #59), we will need corresponding default data. This is a placeholder so that the issue is on our list.

teixeirak commented 8 years ago

Please provide an example of the default data file format, and I will prepare updated default values to correspond to new biomes mapping scheme.

teixeirak commented 8 years ago

A reminder: Please provide an example of the default file format currently used by the calculator for biome default values, and I will prepare updated default values to correspond to new biomes mapping scheme.

teixeirak commented 8 years ago

NOTE: all these instructions are also available in Word file in Box/gcs/revised biomes mapping.

Issue #59, once implemented, will make it such that selection of a location yields a list of one or more broad potential vegetation types. The next step will be to associate these more specifically to climate zones so that it is possible to assign reasonable default model parameters.

DETERMINING BIOME TYPE Treatment of specific crop types (e.g., corn, soy, sugarcane) will not change. What follows are instructions for assigning biome type and default model parameters to the eight natural vegetation types, pasture, and generic crops.

The natural vegetation type categories are:

  1. broadleaf evergreen forest
  2. broadleaf deciduous forest
  3. mixed broadleaf-conifer forest
  4. conifer evergreen forest
  5. conifer deciduous forest
  6. savanna
  7. shrub-dominated
  8. grass-dominated 8b. pasture
  9. crops

(note: category 10, barren, will be listed as a likely cover type, but it will not be selectable as a vegetation type. For specific crop types, treatment will stay as is.).

In order to assign more specific biome types, each of which is associated with default model parameters, the calculator will need to draw upon the Koppen-Geiger map (and FAO ecozones map, in the case of grasses). It will then use the combination of vegetation type and climate to assign a biome, as in the spreadsheet VegType_to_BiomeType.csv (in Box/gcs/revised biomes mapping). This step will give a biome code (e.g., “T1” is trees in tropical rainforest climate). Codes include T1-T13 (13 forest types), S1-S5 (5 shrub/ savanna/ tundra types), G1-G7 (7 grassland types), AP1-AP2 (2 anthropogenic- pasture types), and AC1-AC2 (2 anthropogenic- crops types).

For grasslands and pastures, the calculator will also need to draw on the FAO ecozones map to determine the association. This is also outlined in VegType_to_BiomeType.csv.

Once the biome code is obtained, it will be used to assign default parameters.

ASSIGNMENT OF DEFAULT VALUES Each ecosystem type has an associated set of default model parameters. As of May 15, 2016, these are in the following format: https://github.com/ebimodeling/ghgvc/blob/5b3a06753491ba3ddfc5353e7d96e404e46b8708/public/data/default_ecosystems.json,

New values for each of the revised natural biome types are given in the file biome default “values_natural biomes_May17.csv” (Box/gcs/Revised Biomes Mapping). Default values for pastures and croplands do not change. The codes map as follows: AP1- tropical pasture; AP2- temperate pasture; AC1- tropical cropland; AC2- temperate cropland.

Some notes:

1- There are some parameters that should be controlled in the settings, not associated by biome type. These include T_A, T_E, and r. For these values, the spreadsheet has the value “SETTINGS” rather than numbers. See https://github.com/ebimodeling/ghgvc/issues/12

2- There are a few biome types for which default values do not (yet) exist, as indicated by “NaN”. For these, the calculator should give an error message. Something like: “Insufficient data for this vegetation type in this location. Please enter values manually or de-select this ecosystem type.”

3- For some values, values should automatically be drawn from a map. For these, the spreadsheet has the value “MAP” rather than numbers. These include OM_SOM and biophysical values. Instructions will follow.

4- Most of these values will stay the same, but I will want to revise some. Can this be set up in such a way that I can simply swap out a .csv file or go in and edit a text file?

INSTRUCTIONS FOR OM_SOM For all ecosystem types, the calculator will draw on the HWSD map (Nachtergaele et al., 2010; Hiederer & Köchy, 2011), which is already implemented in the calculator, and will only be slightly modified.

For natural ecosystems and pastures, (a) if SYNMAP = any lifeform but crops, OM_SOM=0.3*(HWSD value for SOC in top meter)

(b) if SYNMAP = crops, OM_SOM=0.43*(HWSD value for SOC in top meter)

For crops, OM_SOM=0

INSTRUCTIONS FOR BIOPHYSICAL VALUES The biophysical maps (IBIS output from Peter Snyder: net radiation, latent heat), which are already implemented in the calculator, are associated with IBIS potential vegetation. These values should only be used when the user selects a vegetation type that corresponds with the modeled data. (Note that this principle will apply to any modeled data that we add.) Match is to be determined based on vegetation type- IBIS biome type associations matrix in VegTypeAssociations.csv (in Box/gcs/Revised Biomes Mapping). If the selected vegetation type corresponds to IBIS potential vegetation (matrix value =1) for that location, it is appropriate to use biophysical values. Otherwise, no biophysical data are available and no biophysical values should be returned.

teixeirak commented 8 years ago

This has been implemented; closing this issue.