This catalogue entry provides daily and monthly global climate projections data from a large number of experiments, models and time periods computed in the framework of sixth phase of the Coupled Model Intercomparison Project (CMIP6).
CMIP6 data are going to be used extensively in the Intergovernmental Panel on Climate Change 6th Assessment Report. The use of these data is mostly aimed at:
- addressing outstanding scientific questions that arose as part of the IPCC reporting process;
- improving the understanding of the climate system;
- providing estimates of future climate change and related uncertainties;
- providing input data for the adaptation to the climate change;
- examining climate predictability and exploring the ability of models to predict climate on decadal time scales;
- evaluating how realistic the different models are in simulating the recent past.
The term "experiments" refers to the three main categories of CMIP5 simulations:
- Historical experiments which cover the period where modern climate observations exist. These experiments show how the GCMs performs for the past climate and can be used as a reference period for comparison with scenario runs for the future. The period covered is typically 1850-2005.
- Climate projection experiments following the combined pathways of Shared Socioeconomic Pathway (SSP) and Representative Concentration Pathway (RCP). The SSP scenarios provide different pathways of the future climate forcing. The period covered is typically 2006-2100, some extended RCP experimental data is available from 2100-2300.
In this catalogue entry the users will be able to select vertical levels for the 3-dimensional variables and spatial and temporal subsetting of all the available data. This is a new feature of the global climate projection dataset, which relies on compute processes run simultaneously in the ESGF nodes, where the data are originally located.
The data are produced by the participating institutes of the CMIP6 project.
| DATA DESCRIPTION | |
|---|---|
| Data type | Gridded |
| Horizontal coverage | Global |
| Horizontal resolution | From 0.125° x 0.125° to 5° x 5° depending on the model |
| Vertical resolution | Variables are provided either in one single level (2-dimensional fields) or in pressure levels (3-dimensional fields) |
| Temporal coverage | 1850-2300 (shorter for some experiments) |
| Temporal resolution | Daily and Monthly |
| File format | NetCDF |
| MAIN VARIABLES | ||
|---|---|---|
| Name | Units | Description |
| Near-Surface Air Temperature | K | Temperature of the air near the surface. |
| Daily Maximum Near-Surface Air Temperature | K | Daily maximum near-surface air temperature. |
| Daily Minimum Near-Surface Air Temperature | K | Daily minimum near-surface air temperature. |
| Daily Maximum Near-Surface Wind Speed | m s-1 | Daily maximum 10m wind speed |
| Surface Temperature | K | Temperature at the interface (not the bulk temperature of the medium above or below) between air and sea for open-sea regions. |
| Sea Level Pressure | Pa | Time average of the air pressure at sea level. |
| Surface Air Pressure | Pa | Pressure of air at the lower boundary of the atmosphere |
| Eastward Near-Surface Wind | m s-1 | Magnitude of the eastward component of the two-dimensional horizontal air velocity near the surface. |
| Northward Near-Surface Wind | m s-1 | Magnitude of the northward component of the two-dimensional horizontal air velocity near the surface. |
| Near-Surface Wind Speed | m s-1 | Magnitude of the two-dimensional horizontal air velocity near the surface. |
| Near-Surface Relative Humidity | % | Amount of moisture in the air near the surface divided by the maximum amount of moisture that could exist in the air at a specific temperature and location. |
| Near-Surface Specific Humidity | Dimensionless | Amount of moisture in the air near the surface divided by amount of air plus moist at that location. |
| Precipitation | kg m-2 s-1 | Amount of water per unit area and time. |
| Snowfall Flux | kg m-2 s-1 | Mass of water in the form of snow precipitating per unit area. |
| Evaporation Including Sublimation and Transpiration | kg m-2 s-1 | Evaporation rate. It includes conversion to vapour phase from both the liquid and solid phase, i.e., includes sublimation. |
| Atmosphere Water Vapor Content | kg m-2 | Vertically integrated water vapor amount through the atmospheric column. |
| Surface Downward Eastward Wind Stress | Pa | Eastward component of the horizontal drag exerted by the atmosphere on the surface through turbulent processes. |
| Surface Downward Northward Wind Stress | Pa | Northward component of the horizontal drag exerted by the atmosphere on the surface through turbulent processes. |
| Surface Upward Latent Heat Flux | W m-2 | Flux per unit area of heat between the surface and the air on account of evaporation including sublimation. Positive when directed upward (negative downward). |
| Surface Upward Sensible Heat Flux | W m-2 | Flux per unit area of heat between the surface and the air by motion of air only. Positive when directed upward (negative downward). |
| Surface Downwelling Longwave Radiation | W m-2 | Radiation inciding on the surface from the above per unit area. |
| Surface Upwelling Longwave Radiation | W m-2 | Longwave radiation from the surface per unit area. |
| Surface Downwelling Shortwave Radiation | W m-2 | Radiative shortwave flux of energy downward at the surface. |
| Surface Upwelling Shortwave Radiation | W m-2 | Shortwave radiation from the surface per unit area. |
| TOA Incident Shortwave Radiation | W m-2 | Incident solar radiation at the top of atmosphere |
| TOA Outgoing Shortwave Radiation | W m-2 | Shortwave radiation from the top of the atmosphere to space per unit area. |
| TOA Outgoing Longwave Radiation | W m-2 | Longwave radiation from the top of the atmosphere to space per unit area. |
| TOA Outgoing Shortwave Flux Assuming Clear Sky | W m-2 | Shortwave radiation from the top of the atmosphere to space per unit area assuming clear-sky conditions. |
| TOA Outgoing Longwave Flux Assuming Clear Sky | W m-2 | Longwave radiation from the top of the atmosphere to space per unit area assuming clear-sky conditions. |
| Total Cloud Cover Percentage | Dimensionless | Total refers to the whole atmosphere column, as seen from the surface or the top of the atmosphere. Cloud cover refers to fraction of horizontal area occupied by clouds. |
| Air Temperature | K | Temperature of the air. |
| Eastward Wind | m s-1 | Magnitude of the eastward component of the two-dimensional horizontal air velocity. |
| Northward Wind | m s-1 | Magnitude of the northward component of the two-dimensional horizontal air velocity. |
| Relative Humidity | % | Amount of moisture in the air divided by the maximum amount of moisture that could exist in the air at a specific temperature and location. |
| Specific Humidity | Dimensionless | Amount of moisture in the air divided by amount of air plus moisture at that location. |
| Geopotential Height | m | Gravitational potential energy per unit mass normalised by the standard gravity at mean sea level at the same latitude. It is also used as vertical coordinate referenced to Earth's mean sea level since its value is proportional to the elevation above the mean sea level. |
| Surface Snow Amount | kg m-2 | Snow amount on the ground, excluding that on the plant or vegetation canopy, per unit area. |
| Snow Depth | m | Mean thickness of snow. |
| Total Runoff | kg m-2 s-1 | Amount per unit area of surface and subsurface liquid water which drains from land. |
| Surface Runoff Flux | kg m-2 s-1 | The total surface runoff leaving the land portion of the grid cell divided by the land area in the grid cell (report as "missing" or 0.0 where the land fraction is 0.). |
| Moisture in Upper Portion of Soil Column | kg m-2 | Vertical sum per unit area from the surface down to the bottom of the soil model of water in all phases contained in soil. |
| Sea-Ice Area Percentage (Ocean Grid) | % | Area of the sea surface occupied by sea ice. |
| Sea Ice Thickness | m | Vertical extent of ocean sea ice. |
| Sea-Ice Mass per Area | kg m-2 | Mass per unit area of sea ice plus snow in the ocean portion of the grid cell averaged over the entire ocean portion, including the ice-free fraction. Reported as 0.0 in regions free of sea ice. |
| Surface Temperature of Sea Ice | K | Temperature that exists at the interface of tea sea-ice and the overlying medium which may be air or snow. |
| Sea Surface Temperature | K | Temperature of sea water near the surface. |
| Sea Surface Salinity | PSU | Salt concentration close to the ocean's surface. |
| Sea Surface Height Above Geoid | m | Vertical distance between the actual sea surface and a surface of constant geopotential with which mean sea level would coincide if the ocean were at rest. |
| Grid-Cell Area for Ocean Variables | m-2 | The area of the grid cell in the ocean. The data is time-independent. |
| Sea Area Percentage | % | The percentage of sea surface in a grid cell. The data is time-independent. |
| Grid-Cell Area for Atmospheric Grid Variables | m-2 | The area of the grid cell in the atmosphere. The data is time-independent. |
| Capacity of Soil to Store Water (Field Capacity) | kg m-2 | The total water holding capacity of all the soil in the grid cell divided by the land area of the grid cell. |
| Percentage of the Grid Cell Occupied by Land (Including Lakes) | % | The percentage of land or lake surface in a grid cell. The data is time-independent. |
| Land Ice Area Percentage | % | Fraction of grid cell occupied by "permanent" ice (e.g. glaciers). The data is time-independent. |
| Surface Altitude | m | The height above the geoid (being 0.0 over the sea). The data is time-independent. |