gÖte-2001: contribution from rcgrcg.gvc.gu.se/posters/gacposter_kb.pdf · gÖte-2001: contribution...
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GÖTE-2001: Contribution from RCG1)Borne, K., 1)Chen, D., 1)Achberger, C.,
1)Miao, J., 2)Wyser, K., 3)Lindgren, J., 2)Langner, J.1)Regional Climate Group, Physical Geography, Earth Sciences Centre, Göteborg University, Sweden
2)SMHI, Norrköping3) City of Göteborg, Environment Administration
IntroductionThe need for co-operation in many areas and disciplines are central in today’s research. Urban studies of the atmosphere and air pollution problems are no exception. In Gothenburg several groups from Göteborg University and Chalmers University of Technology work in the area of atmospheric science, together with research institutes and local environmental authorities.
Intensified cooperation is thus an effective way to increase our understanding of the interaction between atmospheric processes and air quality in Gothenburg. GÖTE-2001, a non-funded joint field campaign initiated by Professor DeliangChen and coordinated by Dr. Katarina Borne is a first and successful attempt in this direction.
The concept of the campaignThe campaign GÖTE-2001 took place during two weeks in May 2001. Everybody having a non-profitable interest in air quality issues was welcome to join the campaign with own instruments, either to conduct meteorological or air chemistry related measurements. The participating groups are listed in the Table below.
The main objective was to perform a joint field campaign stimulating the cooperation among the GÖTE-2001 participants beyond the duration of the field campaign. Creating a database suitable for validation of meteorological models in the Gothenburg region was an important step towards this goal. In addition, each participant could follow individual aims depending on the group’s research interest. Figure 1 presents the “hot spots” of meteorological measurements during GÖTE-2001.
[email protected] Meteorological and Hydrological InstituteJoakim Langner
[email protected] Gothenburg Municipal Environmental Authority, The Air GroupJesper Lindgren
[email protected] Swedish Environmental Research Institute Ltd.Marie Haeger-Eugensson
[email protected] Chemistry,Dept. of Chemistry, GUJan Pettersson
[email protected] Physics, Department of Physics, Chalmers University of Technology/GUMattias Hallquist
[email protected] Climate Group, Earth Sciences Centre, GUIngegärd Eliasson
[email protected], Earth Science Centre, Göteborg University (GU)Katarina Borne
E-mail addressGroups +Contact person
Meteorological data collection RCG conducted meteorological measurements at 4 field stations and collected additional temperature data at 30 different sites.These were distributed as regularly as possible by dividing the region into a grid with cells of size 5*5 km and locating one temperature sensor in each of these cells (see Fig. 1). Surface water temperature was measured in the archipelago of Gothenburg. Mobile measurements by car collected humidity, air and surface temperature data within the city during three days. Figure 2a and b illustrates the field stations on the roof of Earth Sciences Centre and the bridge “Älvsborgsbron” respectively.
Figure 1: Location of meteorological stations. The grid illustrates the layout of the temperature sensor (one in each cell). Blue circles representing RCG, blue squares representing the Urban Climate Group, Urban Climate Physical Geography/Department of Earth Sciences, GU; black circles representing the Swedish Road Administration; black squares representing Swedish Meteorological and Hydrological Institute (SMHI); and dark pink circles representing the Gothenburg Municipal Environmental Authority, The Air Group.
Figure 2a:Wind anemometer and wind vane at the roof of Earth Sciences Centre
Figure 2b:At three levels on the north pilon of the bridge ”Älvsborgsbron” meteorological measurements are performed by Physical Geography/Earth Sciences Centre.
And here are some results......
Figure 4: The spatial distribution of the surface air temperature on the 7th of May at 12:00 pm.
Figure 5: Wind speeds at different height showing the occurrence of a low level jet at Landvetter air port.
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Fig. 4 shows the nigh-time temperature distribution over the city on May 7 2001 at 12:00 pm. The data is collected from 30 temperature sensors distributed according to Fig. 1. A large decreasing temperature gradient from West to East is obvious reflecting the reflecting the development of an urban heat island during that night.
Figure 3: Temperature and wind speed during GÖTE-2001 measured at Skansen Lejonet in the city centre of Gothenburg.
During 6 days sea-breeze circulation (SB) was observed. Fig. 6 present the onset of the SB using wind direction data from four meteorological stations on 8 May. The system progress further inland over time as indicated by a distinct shift in wind direction from south-easterly to westerly winds.
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Figure 6: Sea breeze progress inland during the 8th of May.
For More InformationPlease contact [email protected]. This poster together with the report “Data report on measurements of meteorological- and air pollution variables during the campaign GÖTE-2001; Borne, K., Chen, D., Miao, J., Achberger, C., Lindgren, J., Hallquist, M., Pettersson, J., Haeger-Eugensson, M., Wyser, K., Eliasson, I., Langner, J. is available online at www.gvc.gu.se/rcg
AcknowledgmentsWe acknowledge all the participants in the GÖTE-2001 campaign for making the campaign a starting point for further collaboration. We also are very thankful to the support on technical information and measurement procedures given to us by co-workers to the participants. Lantmäteriet has delivered digital maps which have been very useful.
Meteorological conditions during the campaign
The weather during the first week of the campaign was characterised by anti-cyclonic conditions with fair weather while low-pressure systems lead to more changable weather in the second week. Fig. 3 presents the temperature and wind speed at the station Skansen Lejonet during the period. Note the large diurnal temperature variations and the well-developed daily cycle in wind speeds in the first week. During high-pressure conditions with calm weather, local circulation systems and large spatial temperature gradients during night can develop.
During the night from May 6 to May 7 a low level jet (LLJ) formed. Using radio soundings from the Landvetter air port a vertical profile of wind speeds in different levels is obtained (Fig. 5). The LLJ wind speed maximum is found below 1000 m. Its formation is related to the occurrence of a surface inversion.
GÖTE-2001: Contribution from RCG1)Borne, K., 1)Chen, D., 1)Achberger, C.,
1)Miao, J., 2)Wyser, K., 3)Lindgren, J., 2)Langner, J.1)Regional Climate Group, Physical Geography, Earth Sciences Centre, Göteborg University, Sweden
2)SMHI, Norrköping
3) City of Göteborg, Environment Administration