Analysis Of The Difference Between Automatic And Conventional Observations In Shandong

In this paper,temperature,wind direction and velocity data of 72-pair manual and automatic observations in period of parallel observation in Shandong province are used to calculate temperature difference,wind direction consistence and velocity difference in respect to 5 climate regions,the northwest,middle,southeast,southwest and byland area of Shandong province.On temperature,mean day temperature, maximum and minimum day temperature,and compared difference rate(CDR hereafter) of timing temperature of all the observations and respective regions are computed,meanwhile we statistically collected their frequency distribution,analyzed daily variation pattern of CDR of temperature,and further computed standard error, coarse difference rate and consistence rate of all sorts of CDR and their annual variation.Significance test is computed for mean day temperature,maximum and minimum day temperature of Jinan automatic observation.On wind direction and velocity,firstly,wind direction consistence rate and its annual variation are analyzed statistically for both manual and automatic observations.Then,CDR of timing wind velocity and its annual variation are analyzed with its uncertainty,coarse difference rate and consistence rate.The results of CDR of temperature analysis show that according to mean day temperature,maximum and minimum day temperature,the observed value of automatic observations(A.O hereafter) are higher than that of manual observations (M.O hereafter).At 02am and 20pm,A.Os are mainly lower than M.Os,and at 08am and 14pm,the results are on the contrary.In Xinxian county,A.O is lower than M.O during night,while the situation is opposite during day.In Huimin,Longkou,and Luxian,A.Os are evenly higher than M.Os.Mean day temperature,maximum and minimum day temperature,frequency distribution of CDR of timing temperature,CDR and variation of standard error, coarse difference rate and consistence rate are in accordance without obvious regional difference.According to occurrence frequency of compared temperature difference between ±0.2℃,mean day temperature reached 80%,the highest,maximum day temperature followed by 70%-80%,and minimum day temperature 45%-70%the lowest.At 20pm,the occurrence rate are all above 70%.At 02am,08am,and 14pm,they are mostly below 60%.CDR of mean day temperature and its standard error are the lowest,followed by maximum day temperature,and that of the minimum day temperature are the highest. The coarse difference rate of mean day temperature and maximum day temperature are both below 2%,and that of minimum day temperature is beyond 2%.The consistence rate of CDR of mean day temperature is the highest,then the maximum day temperature,and the minimum day temperature the lowest,but the above three all exceed 90%.Standard error of CDR of timing temperature is maximum at 02am,minimum at 20pm,and its annual variation reaches the minimum in summer.The coarse difference rate is more than 2%at 02am and 20pm,and less than 2%at 08am and 14pm.In northwest of Shandong province,CDR and coarse difference rates of all sorts of temperatures are beyond 2%,and in byisland areas,they are mainly below 2%.The consistence rate in any regions are above 90%,which features highest at 20pm and lowest at 08am.Occurrence frequency of hourly CDR between±0.2℃reaches the highest during night,and lowest during day,the lowest point appears at 08am.CDR of temperature has a smooth variation during night,and a comparatively fierce increase during day, the highest point appears at 08am.The standard errors are generally small during night and big during day which is verified in all seasons.The coarse difference rates are on the contrary,where those less than 2%are concentrated during day,the lowest between 08am and 14pm.The consistence rates are pivotally above 90%with slight variation,while lower during day with obvious change,and hits the lowest rate at 08am.The temperature observed by Jinan A.O shows no significant difference from historical data.Results of wind direction and velocity analysis indicate that in by-island,monthly average values of A.Os are smaller than that of M.Os.In middle of Shandong province,the A.O is higher than M.O,which is also true in most of year in southeast and southwest of Shandong province.Coarse difference rate and consistence rate of CDR of wind velocity of all observations in different regions are in accordance with no obvious regional differences.The consistence rates of timing wind direction are respectively 39.76%at 02am, 38.68%at 08am,37.6%at 14pm,and 39.84%at 20%,which is higher in spring and winter,lower in summer and autumn,and reaches the lowest in autumn.In all observations,the annual average CDR of the wind velocity is beyond 0.2m/s at 02am and 08am,and under 0.2 m/s at 14pm and 20pm.The uncertainty rates of CDR of the wind velocity exceed 1m/s criterion in general.The coarse difference rates are below 2%in most months,and those beyond 2%mainly occur in spring.The consistence rates all stay above 90%.