[CF-metadata] Help needed with area_type and "surface type classification" datasets

From: Seth McGinnis <mcginnis>
Date: Mon, 26 Sep 2011 16:56:13 -0600

 Jonathan Gregory <j.m.gregory at reading.ac.uk> wrote:
>> Do we get enough benefit by "standardizing" them
>> [area-type names] to offset the cost in time and trouble
>> of the growth of yet another complex name hierarchy? (I
>> know. Some people will say "Yes!" I just have to ask.)
>
>It's a fair question. I am one of those who would say
>"Yes"! If it turns out that this becomes a large problem
>which we can't deal with effectively, we will have to think
>again. So far that has not happened.

Hi all,

I would be one who says "No"; I think the area_types system is
too restrictive, and that we should move away from standardized
names for surface classifications. (I do have a replacement
scheme in mind that I would like to float, once I'm not
frantically helping revise a paper.)

But rather than argue the case abstractly, let me propose a test
case that I think will allow us to answer the question
*experimentally*. I actually have data on hand that I've been
pondering how to properly represent under CF.

These are the different land-type classifications used by the
land-surface models (NOAH, BATS, and MOSES) that are part of the
regional climate models we work with. I don't know much about
these classes other than which model they're coming from, and
that they should be stored with a standard_name of "land_cover".

Attached below are the 93 unique values for surface types from
these 3 models. If it looks like we could hash out the details
and extend the existing area_types list could be extended to
cover this list in fairly short order, then I think we can say
that the current system will be sufficient. If it's a bigger
job than that, then I don't think it's adequate.

Does that seem like a fair test? (And note, there's a fourth
land-surface model that I don't have data from. I expect that
when I do get it, I'll have another list of around 20-40 land
types to reconcile with / add to the existing list. So proposed
additions will likely come in big chunks like this, not one or
two at a time.)

Cheers,

--Seth McGinnis


Land-cover types used by land-surface models in NARCCAP:

arable cropland
bare ground tundra
barren or sparsely vegetated
bog or marsh
cane sugar
coffee
cotton
crop/mixed farming
cropland/grassland mosaic
cropland/woodland mosaic
deciduous broadleaf forest
deciduous broadleaf tree
deciduous needleleaf forest
deciduous needleleaf tree
deciduous shrub
deciduous tree crops (temperate)
dense deciduous broadleaf forest
dense deciduous needleleaf forest
dense drought deciduous forest
dense evergreen broadleaf forest
dense mixed evergreen + deciduous forest
dense needleleaf evergreen forest
desert
dry farm arable
dryland cropland and pasture
dwarf shrub (tundra transition + high altitude wasteland)
equatorial rain forest
equatorial tree crop
evergreen broadleaf
evergreen broadleaf cropland
evergreen broadleaf shrub
evergreen broadleaf tree
evergreen broadleaf woodland
evergreen needleleaf
evergreen needleleaf tree
evergreen shrub
forest/field mosaic
grassland
herbaceous tundra
herbaceous wetland
ice
ice cap/glacier
inland water
irrigated crop
irrigated cropland
irrigated cropland and pasture
maize
mangrove (tree swamp)
mixed dryland/irrigated cropland and pasture
mixed forest
mixed shrubland/grassland
mixed tundra
mixed woodland
nursery + market gardening
ocean
open deciduous broadleaf woodland
open deciduous needleleaf woodland
open drought deciduous woodland
open mixed evergreen + deciduous woodland
open needleleaf evergreen forest
open tropical woodland
open water
paddy rice
pasture + shrub
pasture + tree
rough grazing + shrub
sand desert + barren land
savanna
semi arid rough grazing
semi desert + scattered trees
semi-desert
short grass
shrub desert + semi desert
shrubland
snow or ice
tall grass
tea
temperate meadow + permanent pasture
temperate rough grazing
thorn shrub
tropical broadleaf forest (slight seasonality)
tropical grassland + shrub
tropical pasture
tropical savanna (grassland + tree)
tundra
urban
urban and built-up land
vineyard
water and land mixture
water bodies
wooded tundra
wooden wetland
woodland + shrub
Received on Mon Sep 26 2011 - 16:56:13 BST