The original meteorological data is the China Ground Climate Daily Value Dataset (V3.0), from the National Meteorological Information Center China Meteorological Data Network, in. txt format, with a time range of 1971-2020, including key fields such as station number, observation date, daily maximum temperature, daily minimum temperature, and daily precipitation. A total of 346 meteorological station data.

    This study strictly follows the ETCCDI (Expert Group on Climate Change Detection and Indicators) indicator system in the World Meteorological Organization (WMO) Guidelines for Climate Change Detection and Indicators, and is based on daily meteorological observation data from northern China from 1971 to 2020. This dataset covers core elements such as daily maximum temperature, daily minimum temperature, daily precipitation, and sandstorm observation records. Through a multi-step standardized process in the R language environment, 29 core extreme climate indicators were calculated. The extreme wind speed calculation reference (Jiang et al. 2023) paper includes three threshold calculations for extreme wind speed and the number of annual sandstorms. In the specific process, strict data quality control is first implemented on the original meteorological station data, eliminating outliers and missing data to ensure the reliability of basic data; Subsequently, two core methods were used to calculate extreme climate indicators: one was the absolute threshold method, which focused on calculating indicators such as maximum 1-day precipitation (RX1-day) and maximum 5-day precipitation (RX5day) that reflect the characteristics of precipitation extremes; The second method is the relative percentile method, which is used to calculate indicators such as heavy precipitation (R95p), extreme precipitation days (R20mm), precipitation intensity (SDII) that depend on the climate background of the reference period, ensuring the scientific and standardized calculation of indicators. "