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
There are a lot of simulations used in this paper because we used an ensemble physics approach. So there is a mixture of these, plus special simulations
You can have make you own analysis and plots by going here
| Simulation Name as in Paper | Simulation name on web pages |
|---|---|
| PI HadGEM2-A with dynamic vegetation | xgliv |
| LGM HadGEM2-A with dynamic vegetation | xgliu |
| PI HadGEM2-A with fixed modern vegetation | xgseu |
| LGM HadGEM2-A with fixed modern vegetation | xgsew |
| PI HadGEM2-A with veg prescribed from HadCM3M2 | xgsez |
| LGM HadGEM2-A with veg prescribed from HadCM3M2 | xgsex |
| PI HadGEM2-A dynamic vegetation with HadCM3M2 model parameters | xjlaj |
| LGM HadGEM2-A dynamic vegetation with HadCM3M2 model parameters | xjlai |
| PI HadGEM2-A optimal tuned | xjlah |
| LGM HadGEM2-A optimal tuned | xjlag |
This paper demonstrates an example of improving an Earth System model by confronting it with reconstructions of LGM environmental conditions. Specifically we document improvements made to the dynamic vegetation scheme which have major impacts on the resultant LGM climate and dust cycle.
| Name | Hopcroft and Valdes |
|---|---|
| Brief Description | This paper demonstrates an example of improving an Earth System model by confronting it with reconstructions of LGM environmental conditions. Specifically we document improvements made to the dynamic vegetation scheme which have major impacts on the resultant LGM climate and dust cycle. |
| Full Author List | Peter O. Hopcroft and Paul J. Valdes |
| Title | Last glacial maximum constraints on the Earth System Model HadGEM2-ES |
| Year | 2014 |
| Journal | Climate Dynamics |
| Volume | |
| Issue | |
| Pages | |
| DOI | 10.1007/s00382-014-2421-0 |
| Contact's Name | Peter O. Hopcroft |
| Contact's email | peter.hopcroft@bristol.ac.uk |
| Abstract | We investigate the response of the atmospheric and land surface components of the CMIP5/AR5 Earth System model HadGEM2-ES to pre-industrial (PI: AD 1860) and last glacial maximum (LGM: 21 kyr) boundary conditions. HadGEM2-ES comprises atmosphere, ocean and sea-ice components which are interactively coupled to representations of the carbon cycle, aerosols including mineral dust and tropospheric chemistry. In this study, we focus on the atmosphere-only model HadGEM2-A coupled to terrestrial carbon cycle, and aerosol models. This configuration is forced with monthly sea surface temperature and sea-ice fields from equivalent coupled simulations with an older version of the Hadley Centre model, HadCM3. HadGEM2-A simulates extreme cooling over northern continents and nearly complete die back of vegetation in Asia, giving a poor representation of the LGM environment compared with reconstructions of surface temperatures and biome distributions. The model also performs significantly worse for the LGM in comparison with its precursor AR4 model HadCM3M2. Detailed analysis shows that the major factor behind the vegetation die off in HadGEM2-A is a subtle change to the temperature dependence of leaf mortality within the phenology model of HadGEM2. This impacts on both snow-vegetation albedo and vegetation dynamics. A new set of parameters is tested for both the preindustrial and LGM, showing much improved coverage of vegetation in both time periods, including an improved representation of the needle-leaf forest coverage in Siberia for the pre-industrial. The new parameters and the resulting changes in global vegetation distribution strongly impact the simulated loading of mineral dust, an important aerosol for the LGM. The climate response in an abrupt 4× pre-industrial CO2 simulation is also analysed and shows modest regional impacts on surface temperatures across the Boreal zone. |