Paper: Davies-Barnard et al 2014

Title: Sensitivity of a coupled climate model to canopy interception capacity

For a fuller description of the paper itself, go to the end of this web page.

Each simulation published in this paper corresponds to a unique 5 or 6 character code on the web pages.
The following table lists the name of the simulation as used in the paper, and the corresponding code name

The webpage gives you the ability to examine the published simulations, but you can also download the raw (netcdf) files to perform your own analysis. Detailed instructions on how to use the webpages and access the data can be found here: Using_BRIDGE_webpages.pdf

The ensemble explores three values for ground surface capacity: 0 mm (L), 0.5 mm (N) and 2.0 mm (H). For C_C (the canopy capacity which varies with LAI), five values are used: 0.005 (VL), 0.025 (L), 0.05 (N), 0.25 (H), 0.5 (VH). In the EqVeg ensemble the vegetation is able to adapt to the climate, whereas the FixVeg remains with the same vegetation cover throughout.

You can have make you own analysis and plots by going here

Simulation Name as in PaperSimulation name on web pages
canNgN FixVegtdlda
canVLgN FixVegtdldb
canLgN FixVegtdldc
canHgN FixVegtdldd
canVHgN FixVegtdlde
canNgL FixVegtdldf
canVLgL FixVegtdldg
canLgL FixVegtdldh
canHgL FixVegtdldi
canVHgL FixVegtdldj
canNgH FixVegtdldk
canVLgH FixVegtdldl
canLgH FixVegtdldm
canHgH FixVegtdldn
canVHgH FixVegtdldo
canNgN EqVegtdlha
canVLgN EqVegtdlhb
canLgN EqVegtdlhc
canHgN EqVegtdlhd
canVHgN EqVegtdlhe
canNgL EqVegtdlhf
canVLgL EqVegtdlhg
canLgL EqVegtdlhh
canHgL EqVegtdlhi
canVHgL EqVegtdlhj
canNgH EqVegtdlhk
canVLgH EqVegtdlhl
canLgH EqVegtdlhm
canHgH EqVegtdlhn
canVHgH EqVegtdlho


This is a fuller description of paper

Here we present the first research exploring the sensitivity of the climate and surface hydrology to a realistic range of canopy interception capacity parameter values, taken from the literature. We show that this previously ignored parameter significantly affects the mean annual global temperature as much as -0.64 K and locally up to -1.9 K.

NameDavies-Barnard et al.
Brief DescriptionHere we present the first research exploring the sensitivity of the climate and surface hydrology to a realistic range of canopy interception capacity parameter values, taken from the literature. We show that this previously ignored parameter significantly affects the mean annual global temperature as much as -0.64 K and locally up to -1.9 K.
Full Author ListDavies-Barnard T, Valdes PJ, Jones CD, and Singarayer JS
TitleSensitivity of a coupled climate model to canopy interception capacity
Year2014
JournalClimate Dynamics
Volumena
Issue
Pagesna
DOI10.1007/s00382-014-2100-1
Contact's NameT Davies-Barnard
Contact's emailt.davies-barnard@bristol.ac.uk
AbstractThe canopy interception capacity is a small but key part of the surface hydrology, which affects the amount of water intercepted by vegetation and therefore the partitioning of evaporation and transpiration. However, little research with climate models has been done to understand the effects of a range of possible canopy interception capacity parameter values. This is in part due to the assumption that it does not significantly affect climate. Near global evapotranspiration products now make evaluation of canopy interception capacity parameterisations possible. We use a range of canopy water interception capacity values from the literature to investigate the effect on climate within the climate model HadCM3. We find that the global mean temperature is affected by up to -0.64 K globally and -1.9 K regionally. These temperature impacts are predominantly due to changes in the evaporative fraction and top of atmosphere albedo. In the tropics, the variations in evapotranspiration affect precipitation, significantly enhancing rainfall. Comparing the model output to measurements, we find that the default canopy interception capacity parameterisation overestimates canopy interception loss (i.e. canopy evaporation) and underestimates transpiration. Overall, decreasing canopy interception capacity improves the evapotranspiration partitioning in HadCM3, though the measurement literature more strongly supports an increase. The high sensitivity of climate to the parameterisation of canopy interception capacity is partially due to the high number of light rain-days in the climate model that means that interception is overestimated. This work highlights the hitherto underestimated importance of canopy interception capacity in climate model hydroclimatology and the need to acknowledge the role of precipitation representation limitations in determining parameterisations.