The global energy balance as represented in CMIP6 climate models

Abstract. The Global Energy Balance Archive (GEBA) is a database for the central storage of the worldwide measured energy fluxes at the Earth's surface, maintained at ETH Zurich (Switzerland). This paper documents the status of the GEBA version 2017 dataset, presents the new web-interface and user access and reviews the scientific impact that GEBA data had in various applications. GEBA has continuously been expanded and updated and contains in its 2017 version around 2500 stations with 500'000 monthly mean entries of various surface energy balance components. The database contains observations from 15 surface energy flux components, with the most widely measured quantity available in GEBA being the shortwave radiation incident at the Earth's surface (global radiation). Many of the historic records extend over several decades. GEBA contains monthly data from a variety of sources, namely from the World Radiation Data Centre (WRDC) in St. Petersburg, from National Weather Services, from different research networks (BSRN, ARM, SURFRAD), from peer-reviewed publications, project and data reports, as well as from personal communications. Quality checks are applied to test for gross errors in the dataset. GEBA has played a key role in various research applications, such as in the quantification of the global energy balance, in the discussion of the anomalous atmospheric absorption or in the detection of multi-decadal variations in surface solar radiation, known as global dimming and brightening. GEBA is further extensively used for the evaluation of climate models and satellite-derived surface flux products. On a more applied level, GEBA provides the basis for engineering applications in the context of solar power generation, water management, agricultural production and tourism. GEBA is publicly accessible through the internet via www.geba.ethz.ch. Supplementary data are available at doi:10.1594/PANGAEA.873078.

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The Global Energy Balance as represented in CMIP6 climate models

10.5194/egusphere-egu21-1416 ◽

2021 ◽

Author(s):

Martin Wild

Keyword(s):

Energy Balance ◽

Climate Models ◽

Longwave Radiation ◽

Heat Fluxes ◽

Global Climate Models ◽

Global Energy ◽

Global Energy Balance ◽

Clear Sky ◽

Downward Longwave Radiation ◽

Global Mean

A plausible simulation of the global energy balance is a first-order requirement for a credible climate model. In the present study I investigate the representation of the global energy balance in 40 state-of-the-art global climate models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6). In the CMIP6 multi-model mean, the magnitudes of the energy balance components are often in better agreement with recent reference estimates compared to earlier model generations &#160;such as CMIP5 on a global mean basis. However, the inter-model spread in the representation of many of the components remains substantial, often on the order of 10-20 Wm-2 globally, &#160;except for aspects of the shortwave clear-sky budgets, which are now more consistently simulated by the CMIP6 models. The substantial inter-model spread in the simulated global mean latent heat fluxes in the CMIP6 models, exceeding 20% (18 Wm-2), &#160;further implies also large discrepancies in their representation of the global water balance. From a historic perspective of model development over the past decades, the largest adjustments in the magnitudes of the simulated present-day global mean energy balance components occurred in the shortwave atmospheric clear-sky absorption and the surface downward longwave radiation. Both components were gradually adjusted upwards over several model generations, on the order of 10 Wm-2, to reach 73 and 344 Wm-2, respectively in the CMIP6 multi-model means. Thereby, CMIP6 has become the first model generation that largely remediates long-standing model deficiencies related to an overestimation in surface downward shortwave and compensational underestimation in downward longwave radiation in its multi-model mean (Wild 2020).Published in: Wild, M., 2020: The global energy balance as represented in CMIP6 climate models. Clim Dyn 55, 553&#8211;577. https://doi.org/10.1007/s00382-020-05282-7&#160;

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The Global Energy Balance Archive (GEBA) version 2017: a database for worldwide measured surface energy fluxes

Earth System Science Data ◽

10.5194/essd-9-601-2017 ◽

2017 ◽

Vol 9 (2) ◽

pp. 601-613 ◽

Cited By ~ 39

Author(s):

Martin Wild ◽

Atsumu Ohmura ◽

Christoph Schär ◽

Guido Müller ◽

Doris Folini ◽

...

Keyword(s):

Energy Balance ◽

Surface Energy ◽

Climate Models ◽

Global Radiation ◽

Surface Flux ◽

Shortwave Radiation ◽

Measured Quantity ◽

Energy Fluxes ◽

Global Energy ◽

Global Energy Balance

Abstract. The Global Energy Balance Archive (GEBA) is a database for the central storage of the worldwide measured energy fluxes at the Earth's surface, maintained at ETH Zurich (Switzerland). This paper documents the status of the GEBA version 2017 dataset, presents the new web interface and user access, and reviews the scientific impact that GEBA data had in various applications. GEBA has continuously been expanded and updated and contains in its 2017 version around 500 000 monthly mean entries of various surface energy balance components measured at 2500 locations. The database contains observations from 15 surface energy flux components, with the most widely measured quantity available in GEBA being the shortwave radiation incident at the Earth's surface (global radiation). Many of the historic records extend over several decades. GEBA contains monthly data from a variety of sources, namely from the World Radiation Data Centre (WRDC) in St. Petersburg, from national weather services, from different research networks (BSRN, ARM, SURFRAD), from peer-reviewed publications, project and data reports, and from personal communications. Quality checks are applied to test for gross errors in the dataset. GEBA has played a key role in various research applications, such as in the quantification of the global energy balance, in the discussion of the anomalous atmospheric shortwave absorption, and in the detection of multi-decadal variations in global radiation, known as global dimming and brightening. GEBA is further extensively used for the evaluation of climate models and satellite-derived surface flux products. On a more applied level, GEBA provides the basis for engineering applications in the context of solar power generation, water management, agricultural production and tourism. GEBA is publicly accessible through the internet via http://www.geba.ethz.ch. Supplementary data are available at https://doi.org/10.1594/PANGAEA.873078.

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Analysis of temperature and altitude effects on the Global Energy Balance during WLTC

International Journal of Engine Research ◽

10.1177/14680874211034292 ◽

2021 ◽

pp. 146808742110342

Author(s):

Francisco Payri ◽

Jaime Martín ◽

Francisco José Arnau ◽

Sushma Artham

Keyword(s):

Energy Balance ◽

Ambient Temperature ◽

Fuel Consumption ◽

Experimental Measurements ◽

Compression Ignition ◽

Oil Viscosity ◽

Compression Ignition Engine ◽

Global Energy ◽

Global Energy Balance ◽

L Compression

In this work, the Global Energy Balance (GEB) of a 1.6 L compression ignition engine is analyzed during WLTC using a combination of experimental measurements and simulations, by means of a Virtual Engine. The energy split considers all the relevant energy terms at two starting temperatures (20°C and 7°C) and two altitudes (0 and 1000 m). It is shown that reducing ambient temperature from 20°C to −7°C decreases brake efficiency by 1% and increases fuel consumption by 4%, mainly because of the higher friction due to the higher oil viscosity, while the effect of increasing altitude 1000 m decreases brake efficiency by 0.8% and increases fuel consumption by 2.5% in the WLTC mainly due to the change in pumping. In addition, GEB shows that ambient temperature is affecting exhaust enthalpy by 4.5%, heat rejection to coolant by 2%, and heat accumulated in the block by 2.5%, while altitude does not show any remarkable variations other than pumping and break power.

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