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"Yu Xue Fen Cun" records during the Qing Dynasty are used to identify the starting and ending dates of Meiyu at the period of 1736-1911. These results, along with the instrumental meteorological records, are used to reconstruct the series of length and precipitation of Meiyu during 1736-2000 over the middle and lower reaches of the Yangtze River. The characteristics of Meiyu are analyzed since 1736. Moreover, the strength of East Asian Summer Monsoon and locations of rainband are discussed, based on the relationship between the length of Meiyu and the Index of East Asian Summer Monsoon. It is found that the starting and ending dates and the length of Meiyu have significant interannual and interdecadal variations. Apart from 7-8 years, 20-30 years and 40 years cycles for the lengths of Meiyu, the centennial oscillation is also presented. The length of Meiyu, monsoon rainband movement over eastern China, and the strength of East Asian Summer Monsoon (EASM) have a very good correlation, which can be expressed in the following: during the periods of 1736-1770, 1821-1870 and 1921-1970, the EASM was stronger, and the monsoon rainband was located in North China and South China easily, corresponding to the decreased length of Meiyu. Whereas during the periods of 1771-1820, 1871-1920 and 1971-2000, the EASM was weaker and monsoon rainband usually stopped at the middle and lower reaches of the Yangtze River, corresponding to the increased length of Meiyu. [ABSTRACT FROM AUTHOR]

It still remains uncertainty whether China's future investment is conducive to carbon reduction of Belt and Road (B&R) region or not. Here, the possible impact of China's investment was revealed by comparing the CO 2 emissions of B&R region in different Chinese investment scenarios. The results showed that CO 2 emissions of B&R region will cumulatively increase by 1973 Gt in 2018–2100 in the "No-Chinese Investment Scenario (NIS)". Regionally, the India (IND), Middle East Central Asia (MECAsia), and Southeast Asia and its surrounding (SEAsia) has the largest increment. Comparing with the NIS, the CO 2 emissions of B&R region will cumulatively decrease by 44.16 Gt and 79.48 Gt, respectively, in the "Business-as-usual Chinese Investment Scenario (BIS)" and "Strengthening Chinese Investment Scenario (SIS)". Regionally, the cumulative CO 2 emissions of all subregions will decrease in BIS and SIS, of which SEAsia and MECAsia have the largest decrement. Technique and structural effects of China's investment have positive impact on cumulative CO 2 emission reduction of B&R region, especially in the structural effect. The scale effect has the negative contribution, but it cannot neutralize the positive impact induced from technique and structural effects. As a result, China's future investment is conductive to reducing CO 2 emission of B&R region and holding the temperature increase below 2 °C. [ABSTRACT FROM AUTHOR]

Large-scale palaeoclimate reconstructions can be very sensitive to the proxy records they are based on, and hence to the criteria used to select proxy records. Data selection rarely follows objective criteria that are applicable to all types of proxies, including both low- and high-resolution records. Thus, there is a need for a uniform and transparent approach to assess the suitability of input proxy data for a reconstruction. Here, we develop classification criteria that are applicable to multiple proxy types and evaluate different selection strategies using a network of 62 millennium-long terrestrial hydroclimate proxy records from Monsoon Asia. Our results reveal that robust evidence for a coherent climate signal and high dating accuracy are important criteria for benchmarking the suitability of each proxy record. We determine these criteria by reviewing the literature for each record (rather than screening against instrumental data). We show that the proposed selection approach can yield a network with a stronger common signal. By evaluating the uncertainty and centennial variability of composite reconstructions, from differently selected subsets of the proxy network, it appears beneficial to use suitable proxies stemming from different archives, as well as having a dense network of proxy sites. We suggest that future large-scale palaeoclimate reconstructions might be improved by evaluating proxy networks according to the universal categories presented here and, if indicated, removing less suitable records. This will strengthen the climate signal in the final reconstruction, allowing more precise inferences about past climate variability and more robust comparisons with climate model simulations. • Suitability of proxy records should be estimated based on literature review. • Semi-quantitative criteria: evidence for climate signal and dating accuracy. • Proposed selection approach can yield a network with a stronger common signal. • Multi-proxy approach is beneficial to preserve various frequency domains. [ABSTRACT FROM AUTHOR]

From a cursory reading of Li & Yang's comments [[6], henceforth LY2019] on our recent review article, [13] [henceforth S2018], some readers might think that LY2019 is somehow disputing our analysis and conclusions. In their Section 1.2, LY2019 claim that there are "only about 200 stations totally in China" in both version 3 and version 4 of the Global Historical Climatology Network (GHCN) dataset. At the end of the section, we will show that whichever school-of-thought you favour, LY2019 were still wrong in their Section 1.3 to dismiss the significance of the comparison between observed trends and the CMIP5 multi-model ensemble average hindcast. In other words, the average Chinese temperature trends hindcasted by the CMIP5 models is determined almost entirely by the choice of forcing datasets used by the modelling groups. [Extracted from the article]