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PardeeCenterDU / IFs-Issues-Tracking

This repository only holds the list of bugs that have been reported for IFs. Anyone may add a bug report, but please look to see if your issue has already been added!
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question on yield (YL) initialization #286

Open quciet opened 8 months ago

quciet commented 8 months ago

Some contexts here, due to the SSP work, fellows found a paper that summarizes crop yield across different models and SSPs, https://doi.org/10.1016/j.gloenvcha.2020.102120. In the data provided by this paper, values are aggregated by regions & crop types, quoted below, "In this study, we apply an aggregation to 6 regions (see SI Supplementary Table 1), while the crop categories are retained: wheat, rice, and maize plus other cereal grains (denoted as ‘coarse grains’). Besides these crops, we also report weighted average yields (based on harvested areas) of all cereals."

Currently, our crop yield is being initialized by crop production and crop land, both from FAO. image In IFs, the Crop category is consisted of following items from the FAO FoodBalanceSheet database, Alcohol, Non-Food Cereals - Excluding Beer Starchy Roots Sugar Crops Sugar & Sweeteners Pulses Treenuts Oilcrops Vegetable Oils Vegetables Fruits - Excluding Wine Stimulants Spices Alcoholic Beverages Miscellaneous

Hence, we take the sum of all crop productions above and divide that by the total crop land to get the crop yield, which is very different than the weighted average yields concept mentioned by that paper. Then I was thinking if we could derive the weighted average yield from FAO's database, but I found out that they are using different coding schemes across datasets.

Previsouly, we collect production data from FAO Food Balance Sheet and crop land data from their Land Use database. However, to calculate a weighted average, we will need to collect harvested area by crop types. I later discovered that FAO has a Crops and livestock products database, https://www.fao.org/faostat/en/#data/QCL, that does exactly this. However, their aggregation of crops through CPC coding system looks different than what are being provided by FAO FBS (FBS uses FBS coding system).

My quetions are,

  1. Should we pursue the path of calculating a weighted average yield for crops?
  2. If so, what would be the approach?
jonathandmoyer commented 6 months ago

I'm lowering this because it's going to be complicated to approach and we're not focused on ag model related academic work... but I agree this should be on the list.