The Interaction Between The Urban Heat Island And The Sea And Land Breeze In Qingdao Based On WRF

Cities in coastal areas are affected by urban heat island(UHI)and coastal sea-land breeze(SLB),which has an impact on the cities and surroundings.Especially,the cities in the coastal areas of China,which are located in the monsoon circulation area,are also affected by large-scale monsoon circulation.In this paper,Qingdao,a coastal city in northern China,is chosen to explore the interaction between UHI and SLB in the context of monsoon circulation,which can not only enrich the research theory of SLB and UHI,but also provide reference for improving the living environment of cities and its surrounding areas.Meanwhile,in recent years,the development of geographic information technology,remote sensing technology and mesoscale numerical simulation model has provided the technical support for the enrichment of geospatial data and mesoscale climate simulation.This paper is based on meteorological observation data,the land use data,landast remote sensing image data and NCEP-FNL global reanalysis data,relying on RS,GIS technology and WRF model,using the method of correlation coefficient analysis,land use data interpretation and processing,numerical simulation and other methods to design the simulation scheme.Then,the best scheme for the simulation effect of the study area was selected.Based on analyzing the interaction between UHI and SLB in Qingdao,the main conclusions are as follows:(1)The combination of different parameterized schemes has a significant impact on the simulation effect of the meteorogical field.And the simulation scheme of the study area was determined by the scheme optimization.The parameterized combination scheme is as follows: WSM 3-class microphysical + YSU boundary layer scheme + Revised MM5 Monin-Obukhov near-surface scheme + Kain-Fritsch cumulus convection scheme + RRTM long-wave radiation scheme + Dudhia short-wave radiation scheme + Unified Noah land-surface process scheme.The land use data is LUCC2015 provided by the Academy of Sciences with land use data.The spatial resolution of the simulation is 3km.The correlation coefficient between wind speed simulation and observation is from 0.5 to 0.75,and the root-mean-square error is less than 1.61.The correlation coefficient between the simulated temperature and the observed value is above 0.82,and the root-mean-square error is less than 2.50.(2)The influence of SLB in different seasons on the scope of UHI is different.In the summer,with strong SLB,the UHI range on SLB days was reduced compared with the average range of this season.(3)Winter and spring sea breeze circulation makes the time of UHI appear earlier and disappear later,and the time and time of UHI increase;In summer and autumn,the sea breeze circulation has no obvious influence on the time of the appearance and disappearance of UHI.Land breeze is strong to UHI with the development of the sea breeze circulation,the wind speed becomes larger and larger,and the mitigation effect on the UHI becomes more and more obvious.(4)The impact of urban heat island on the sea wind is relatively obvious,while the impact on the land wind is not significant.Under the farmland test,the UHI weakened,the urban dynamic effect(friction)became smaller,the intensity of sea breeze increased,and the influence range increased.Under the urban experiment,the UHI was strengthened,the urban dynamic effect(friction)was increased,the sea breeze was strengthened before reaching the city,and weakened after reaching the city,and the influence range of the sea breeze was reduced.It can be seen that in terms of surface wind field,the influence of urban dynamic effect on sea and land wind is greater than that of thermal effect,which is particularly obvious in summer.The enhancement effect of sea and land wind on daily farmland test in summer is more obvious than that of urban test.(5)From the perspective of vertical structure,the change of UHI intensity affects the vertical structure of sea breeze in spring and summer is greater than in autumn and winter.These changes conclude that the UHI weakens,the vertical structure of the sea breeze circulation becomes thinner,and the UHI strengthens and the vertical structure becomes thicker.Moreover,the influence of UHI intensity on the vertical structure is more obvious than that on the horizontal structure.