Analysis Of Future Climate Change In The Belt And Road Under Different Scenarios

The spatial resolution of the global climate model is relatively large,and there are also large errors in the observed values,which cannot be directly applied to the evaluation model.In this paper,we used the quantile mapping method and the perturbation method to correct the surface air temperature and precipitation simulated by the global climate model(HadGEM2-ES)to reduce the error between the model and the observation.At the same time,the higher spatial resolution observation data(CRU and ERA-interim)was used as a sample to establish the correction function,and the resolution of the corrected analog value was improved.On this basis,the simulated values were used to analyze the climate change in the Belt and Road region in the future from 2020 to 2099.The results showed that.(1)After the correction,the linear warming trend of RCP2.6 scenario was the smallest,RCP6.0 was slightly larger than RCP4.5,and the warming trend of RCP8.5was the largest.In RCP4.5 and RCP6.0,the temperature increase was significant before 2055.After that,in RCP4.5,9 regions showed signs of slowing down,with regional differences in slowing time.In RCP6.0,fewer regions showed slowing down,and the slowing time was later.(2)In the extreme daily maximum temperature change in 20 a in the future,the RCP8.5 scenario in Africa and west Asia has the largest temperature increase in the first 40 years,and there is indeed a certain increase in Europe.The four scenarios have little difference,while the East Asia and China have a large increase in the three scenarios of RCP4.5,RCP6.5 and RCP8.5.In the next 40 years,RCP2.6 has not changed much compared to the previous 40 years,while the other three scenarios have increased significantly.The increase of extreme daily minimum temperature is larger than that of daily maximum temperature,and the conclusion is more reliable.(3)After the revision,most of the four scenarios in east Asia,southeast Asia andRussia show an increasing trend,while most of the four scenarios in north Africa and west Asia show a decreasing trend,and the differences between different scenarios in other regions are relatively complex.In the change of extreme daily precipitation in20 a in the future,the extreme precipitation in the first 40 years increased slightly,and the increase was more obvious in the last 40 years.The changes in the RCP2.6scenario are relatively insignificant,and the other three scenarios increase significantly.The increased areas also include those areas where average precipitation is reduced.(4)In the change of drought frequency,in the future RCP4.5 scenario,the frequency of light drought,moderate drought and severe drought all decreased in the junction of eastern Africa,east Asia and central Asia and northern Russia.The frequency of extreme drought decreased significantly in East Africa,west Asia,Arabian Peninsula and Xinjiang.In this scenario,in the future,the frequency of 2successive droughts,3 successive droughts and 4 successive droughts in the junction of East Africa,East Asia and central Asia will decrease.The frequency of successive droughts increased in Europe and north China.There is a decreasing trend of drought in the Arabian peninsula of west Asia.The fifth consecutive drought decreased in North Africa,East Africa and west Asia,but increased by 12.5% in central Asia.