Updated vegetation information in high resolution WRF simulations

Joakim Refslund Nielsen, Ebba Dellwik, Andrea N. Hahmann, Eva Boegh

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review

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Abstract

Climate studies show that the frequency of heat wave events and above-average high temperatures during the summer months over Europe will increase in the coming decades. Such climatic changes and long-term meteorological conditions will impact the seasonal development of vegetation and ultimately modify the energy distribution at the land surface. In weather and climate models it is important to represent the vegetation variability accurately to obtain reliable results. The weather research and forecasting (WRF) model uses green vegetation fraction (GVF) time series to represent vegetation seasonality. The GVF of each grid cell is additionally used to scale other parameters such as LAI, roughness, emissivity and albedo within predefined intervals. However, the default GYP used by WRF does not reflect recent climatic changes or change in management practices since it was derived more than 20 years ago. In this study, a new high resolution GYP product based on MODIS images is applied in a high resolution WRF simulation over Denmark during the 2006 heat wave year. It is found that the GYP is very different in a heat wave year compared to the default GVF. The simulation is compared to a control run using the default GVF data and their performances are quantified against gridded data. The verification includes 2-m temperature and precipitation. The results show that although the simulation using the new GYP product performs well, it does not significantly improve performance compared to the default GYP, despite significant differences in vegetation fractions.
Original languageEnglish
Title of host publicationClimate and Land Surface Changes in Hydrology. Proceedings
Number of pages6
PublisherIAHS Press
Publication date2013
Pages233-238
Publication statusPublished - 2013
EventIAHS - IAPSO - IASPEI Joint Assembly - Gothenburg, Sweden
Duration: 22 Jul 201326 Jul 2013

Conference

ConferenceIAHS - IAPSO - IASPEI Joint Assembly
CountrySweden
CityGothenburg
Period22/07/201326/07/2013
SeriesIAHS Publications Series (Red Books)
Number359
ISSN0144-7815

Keywords

  • GEOSCIENCES,
  • METEOROLOGY
  • WATER
  • CLIMATE-CHANGE
  • VARIABILITY
  • EUROPE
  • green vegetation fraction
  • WRF
  • heat wave

Cite this

Nielsen, J. R., Dellwik, E., Hahmann, A. N., & Boegh, E. (2013). Updated vegetation information in high resolution WRF simulations. In Climate and Land Surface Changes in Hydrology. Proceedings (pp. 233-238). IAHS Press. IAHS Publications Series (Red Books), No. 359
Nielsen, Joakim Refslund ; Dellwik, Ebba ; Hahmann, Andrea N. ; Boegh, Eva. / Updated vegetation information in high resolution WRF simulations. Climate and Land Surface Changes in Hydrology. Proceedings. IAHS Press, 2013. pp. 233-238 (IAHS Publications Series (Red Books); No. 359).
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abstract = "Climate studies show that the frequency of heat wave events and above-average high temperatures during the summer months over Europe will increase in the coming decades. Such climatic changes and long-term meteorological conditions will impact the seasonal development of vegetation and ultimately modify the energy distribution at the land surface. In weather and climate models it is important to represent the vegetation variability accurately to obtain reliable results. The weather research and forecasting (WRF) model uses green vegetation fraction (GVF) time series to represent vegetation seasonality. The GVF of each grid cell is additionally used to scale other parameters such as LAI, roughness, emissivity and albedo within predefined intervals. However, the default GYP used by WRF does not reflect recent climatic changes or change in management practices since it was derived more than 20 years ago. In this study, a new high resolution GYP product based on MODIS images is applied in a high resolution WRF simulation over Denmark during the 2006 heat wave year. It is found that the GYP is very different in a heat wave year compared to the default GVF. The simulation is compared to a control run using the default GVF data and their performances are quantified against gridded data. The verification includes 2-m temperature and precipitation. The results show that although the simulation using the new GYP product performs well, it does not significantly improve performance compared to the default GYP, despite significant differences in vegetation fractions.",
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Nielsen, JR, Dellwik, E, Hahmann, AN & Boegh, E 2013, Updated vegetation information in high resolution WRF simulations. in Climate and Land Surface Changes in Hydrology. Proceedings. IAHS Press, IAHS Publications Series (Red Books), no. 359, pp. 233-238, IAHS - IAPSO - IASPEI Joint Assembly, Gothenburg, Sweden, 22/07/2013.

Updated vegetation information in high resolution WRF simulations. / Nielsen, Joakim Refslund; Dellwik, Ebba; Hahmann, Andrea N.; Boegh, Eva.

Climate and Land Surface Changes in Hydrology. Proceedings. IAHS Press, 2013. p. 233-238 (IAHS Publications Series (Red Books); No. 359).

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review

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T1 - Updated vegetation information in high resolution WRF simulations

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AU - Hahmann, Andrea N.

AU - Boegh, Eva

PY - 2013

Y1 - 2013

N2 - Climate studies show that the frequency of heat wave events and above-average high temperatures during the summer months over Europe will increase in the coming decades. Such climatic changes and long-term meteorological conditions will impact the seasonal development of vegetation and ultimately modify the energy distribution at the land surface. In weather and climate models it is important to represent the vegetation variability accurately to obtain reliable results. The weather research and forecasting (WRF) model uses green vegetation fraction (GVF) time series to represent vegetation seasonality. The GVF of each grid cell is additionally used to scale other parameters such as LAI, roughness, emissivity and albedo within predefined intervals. However, the default GYP used by WRF does not reflect recent climatic changes or change in management practices since it was derived more than 20 years ago. In this study, a new high resolution GYP product based on MODIS images is applied in a high resolution WRF simulation over Denmark during the 2006 heat wave year. It is found that the GYP is very different in a heat wave year compared to the default GVF. The simulation is compared to a control run using the default GVF data and their performances are quantified against gridded data. The verification includes 2-m temperature and precipitation. The results show that although the simulation using the new GYP product performs well, it does not significantly improve performance compared to the default GYP, despite significant differences in vegetation fractions.

AB - Climate studies show that the frequency of heat wave events and above-average high temperatures during the summer months over Europe will increase in the coming decades. Such climatic changes and long-term meteorological conditions will impact the seasonal development of vegetation and ultimately modify the energy distribution at the land surface. In weather and climate models it is important to represent the vegetation variability accurately to obtain reliable results. The weather research and forecasting (WRF) model uses green vegetation fraction (GVF) time series to represent vegetation seasonality. The GVF of each grid cell is additionally used to scale other parameters such as LAI, roughness, emissivity and albedo within predefined intervals. However, the default GYP used by WRF does not reflect recent climatic changes or change in management practices since it was derived more than 20 years ago. In this study, a new high resolution GYP product based on MODIS images is applied in a high resolution WRF simulation over Denmark during the 2006 heat wave year. It is found that the GYP is very different in a heat wave year compared to the default GVF. The simulation is compared to a control run using the default GVF data and their performances are quantified against gridded data. The verification includes 2-m temperature and precipitation. The results show that although the simulation using the new GYP product performs well, it does not significantly improve performance compared to the default GYP, despite significant differences in vegetation fractions.

KW - GEOSCIENCES,

KW - METEOROLOGY

KW - WATER

KW - CLIMATE-CHANGE

KW - VARIABILITY

KW - EUROPE

KW - green vegetation fraction

KW - WRF

KW - heat wave

M3 - Article in proceedings

T3 - IAHS Publications Series (Red Books)

SP - 233

EP - 238

BT - Climate and Land Surface Changes in Hydrology. Proceedings

PB - IAHS Press

ER -

Nielsen JR, Dellwik E, Hahmann AN, Boegh E. Updated vegetation information in high resolution WRF simulations. In Climate and Land Surface Changes in Hydrology. Proceedings. IAHS Press. 2013. p. 233-238. (IAHS Publications Series (Red Books); No. 359).