Land Use Downscaling & Harmonization with

mrdownscale

Florian Humpenöder & Jan Philipp Dietrich

LU downscaling & harmonization via mrdownscale

R software package

Open Source
LGPL3 license

Facilitate reproducibility through sharing of data processing workflows 

reusable through standardization

Improve robustness through integrated testing

more transparent through automatic metadata generation and handling

Builds on MADRaT

Reproducibility

Sharing the data of a study is important 

Sharing the code which produced the data is even more important 

# Stylized representation of data retrieval
install.packages("mrdownscale")
library(mrdownscale)
downscaleRunESM(outputdir = "/my/path/to/the/data")

Reusability

Build on existing code instead of existing data

Use existing pieces in new workflows

Robustness

Testing helps to identify problems in an early stage

Are the values within the expected range?

Is the data in the expected format?

Does the data contain NAs?

mrdownscale:::calcLandInput
[✓] Dimensions are named correctly
[✓] Land input categories match the corresponding mapping
[✓] All values are >= 0
[✓] Total area is constant over time (maxdiff = 3e-08, threshold = 1e-04)
[✓] primforest is never expanding

toolResolutionMapping
[!] 4.7% of input cells missing in target, these are discarded
[!] 0.59% of target cells missing in mapping, adding those to mapping (nearest neighbor)
[!] nearest neighbor distances: max = 737.7km, 90% quantile = 43.9km, mean = 41km

Structured data processing

powered by madrat » github.com/pik-piam/madrat

retrieveData: bundle data sets

readSource: download and read source data 

calcOutput: perform calculations on the data (filtering, merging,...)

data processing split into distinct steps

wrapper provide controlled environment  for user-written code

wrapper 

user code

Building workflows

powered by madrat » github.com/pik-piam/madrat

use building blocks to create data processing workflows

remix existing workflows

reuse snippets from other workflows

The mrdownscale package

land use pipeline 

  1. Flexilibty on inputs (LUH2, MAgPIE)
  2. Mapping of model land cover classes to reference (e.g. crops)
  3. Mapping of model grid cells (low-res) to 0.25 deg
  4. Aggregation of LUH2 to low-res
  5. Harmonizaton (temporal fade-over) of historic and future data sets at low-res
  6. Downscaling of full time-series to 0.25 deg

Historic land use

Future land use

Outputs in standardized LUH2 format

States

c3ann  c3nfx
c3per  c4ann
c4per  pastr
primf  primn
range  secdf
secdn  urban
secma  secmb

Management

crpbf_c3ann  crpbf_c3nfx
crpbf_c3per  crpbf_c4ann
crpbf_c4per  crpbf2_c3per
crpbf2_c4per
  irrig_c3ann
irrig_c3nfx  irrig_c3per
irrig_c4ann  irrig_c4per

manaf  fulwd
rndwd  fertl_c3ann
fertl_c3nfx  fertl_c3per
fertl_c4ann  fertl_c4per
combf  flood
fharv_c3per
  fharv_c4per

Transitions

transitions between all states

crpbf2_c3per crpbf2_c4per

2nd gen biofuel as share of c3per/c4per

manaf

managed forest as
share of secdf

New variables

Further Reading

This presentation - slides.com/jandietrich/mrdownscale

MADRaT repository - https://github.com/pik-piam/madrat
mrdownscale repository - https://github.com/pik-piam/mrdownscale

 

MADRaT tutorial | pik-piam.r-universe.dev/articles/madrat/madrat.html
other MADRaT-based packages | github.com/pik-piam?q=mr                                                   

 

 

        contact | Florian Humpenöder humpenoeder@pik-potsdam.de
Jan Dietrich dietrich@pik-potsdam.de                             

mrdownscale

By Jan Dietrich

mrdownscale

Brief introduction to the Land Use downscaling and harmonization pipeline mrdownscale

  • 42