On the computation of planetary boundary-layer height using the bulk Richardson number method
Experimental data from four field campaigns are used to explore the variability of the bulk Richardson number of the entire planetary boundary layer (PBL), <i>Ri</i><sub>bc</sub>, which is a key parameter for calculating the PBL height (PBLH) in numerical weather and climate...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2014-11-01
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| Series: | Geoscientific Model Development |
| Online Access: | http://www.geosci-model-dev.net/7/2599/2014/gmd-7-2599-2014.pdf |
| _version_ | 1819090568554217472 |
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| author | Y. Zhang Z. Gao D. Li Y. Li N. Zhang X. Zhao J. Chen |
| author_facet | Y. Zhang Z. Gao D. Li Y. Li N. Zhang X. Zhao J. Chen |
| author_sort | Y. Zhang |
| collection | DOAJ |
| description | Experimental data from four field campaigns are used to explore the
variability of the bulk Richardson number of the entire planetary boundary
layer (PBL), <i>Ri</i><sub>bc</sub>, which is a key parameter for
calculating the PBL height (PBLH) in numerical weather and climate models
with the bulk Richardson number method. First, the PBLHs of three different
thermally stratified boundary layers (i.e., strongly stable boundary layers,
weakly stable boundary layers, and unstable boundary layers) from the four
field campaigns are determined using the turbulence method, the potential
temperature gradient method, the low-level jet method, and the modified
parcel method. Then for each type of boundary layer, an optimal
<i>Ri</i><sub>bc</sub> is obtained through linear fitting and statistical
error minimization methods so that the bulk Richardson method with this
optimal <i>Ri</i><sub>bc</sub> yields similar estimates of PBLHs as the
methods mentioned above. We find that the optimal <i>Ri</i><sub>bc</sub>
increases as the PBL becomes more unstable: 0.24 for strongly stable boundary
layers, 0.31 for weakly stable boundary layers, and 0.39 for unstable
boundary layers. Compared with previous schemes that use a single value of
<i>Ri</i><sub>bc</sub> in calculating the PBLH for all types of boundary
layers, the new values of <i>Ri</i><sub>bc</sub> proposed by this study
yield more accurate estimates of PBLHs. |
| first_indexed | 2024-12-21T22:25:54Z |
| format | Article |
| id | doaj.art-8d302eaf8d30448ea73661d10552432c |
| institution | Directory Open Access Journal |
| issn | 1991-959X 1991-9603 |
| language | English |
| last_indexed | 2024-12-21T22:25:54Z |
| publishDate | 2014-11-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Geoscientific Model Development |
| spelling | doaj.art-8d302eaf8d30448ea73661d10552432c2022-12-21T18:48:13ZengCopernicus PublicationsGeoscientific Model Development1991-959X1991-96032014-11-01762599261110.5194/gmd-7-2599-2014On the computation of planetary boundary-layer height using the bulk Richardson number methodY. Zhang0Z. Gao1D. Li2Y. Li3N. Zhang4X. Zhao5J. Chen6International Center for Ecology, Meteorology & Environment, Jiangsu Key Laboratory of Agricultural Meteorology, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, ChinaState Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, ChinaProgram of Atmospheric and Oceanic Sciences, Princeton University, Princeton, NJ 08540, USAInternational Center for Ecology, Meteorology & Environment, Jiangsu Key Laboratory of Agricultural Meteorology, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, ChinaSchool of Atmospheric Sciences, Nanjing University, Nanjing, 210093, ChinaInternational Center for Ecology, Meteorology & Environment, Jiangsu Key Laboratory of Agricultural Meteorology, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, ChinaInternational Center for Ecology, Meteorology & Environment, Jiangsu Key Laboratory of Agricultural Meteorology, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, ChinaExperimental data from four field campaigns are used to explore the variability of the bulk Richardson number of the entire planetary boundary layer (PBL), <i>Ri</i><sub>bc</sub>, which is a key parameter for calculating the PBL height (PBLH) in numerical weather and climate models with the bulk Richardson number method. First, the PBLHs of three different thermally stratified boundary layers (i.e., strongly stable boundary layers, weakly stable boundary layers, and unstable boundary layers) from the four field campaigns are determined using the turbulence method, the potential temperature gradient method, the low-level jet method, and the modified parcel method. Then for each type of boundary layer, an optimal <i>Ri</i><sub>bc</sub> is obtained through linear fitting and statistical error minimization methods so that the bulk Richardson method with this optimal <i>Ri</i><sub>bc</sub> yields similar estimates of PBLHs as the methods mentioned above. We find that the optimal <i>Ri</i><sub>bc</sub> increases as the PBL becomes more unstable: 0.24 for strongly stable boundary layers, 0.31 for weakly stable boundary layers, and 0.39 for unstable boundary layers. Compared with previous schemes that use a single value of <i>Ri</i><sub>bc</sub> in calculating the PBLH for all types of boundary layers, the new values of <i>Ri</i><sub>bc</sub> proposed by this study yield more accurate estimates of PBLHs.http://www.geosci-model-dev.net/7/2599/2014/gmd-7-2599-2014.pdf |
| spellingShingle | Y. Zhang Z. Gao D. Li Y. Li N. Zhang X. Zhao J. Chen On the computation of planetary boundary-layer height using the bulk Richardson number method Geoscientific Model Development |
| title | On the computation of planetary boundary-layer height using the bulk Richardson number method |
| title_full | On the computation of planetary boundary-layer height using the bulk Richardson number method |
| title_fullStr | On the computation of planetary boundary-layer height using the bulk Richardson number method |
| title_full_unstemmed | On the computation of planetary boundary-layer height using the bulk Richardson number method |
| title_short | On the computation of planetary boundary-layer height using the bulk Richardson number method |
| title_sort | on the computation of planetary boundary layer height using the bulk richardson number method |
| url | http://www.geosci-model-dev.net/7/2599/2014/gmd-7-2599-2014.pdf |
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