China's reconstruction of photosynthetically active radiation data collection (1961-2014)

Photosynthetically active radiation (PAR) plays important roles in ecology, agriculture and climatology research. It is a fundamental physiological variable that influence on the vegetation structure and exchange processes of mass and energy. As an important climatic resource, PAR is an indispensable data for calculated the potential photosynthesis, potential yield, crop growth and carbon cycle. In situ measured data from Chinese ecology research network used to develop the estimation model for estimation PAR under all-sky condition. The “hybrid model” was used to calculate historical solar radiation from China Meteorological Administration routine observations. And then combined PAR estimation model that based on clearness index, solar elevation angle and sunshine durations, to obtain the historical daily PAR data at 724 routine stations from 1961 to 2014.

光合有效辐射（Photosynthetically Active Radiation，PAR）在生态学、农业与气候学研究中发挥着关键作用。它是影响植被结构以及物质与能量交换过程的核心生理变量。作为重要的气候资源，光合有效辐射是计算潜在光合能力、潜在产量、作物生长及碳循环不可或缺的基础数据。本研究依托中国生态研究网络的原位实测数据，构建全天空条件下的光合有效辐射估算模型：首先采用混合模型（Hybrid Model），基于中国气象局常规观测资料计算历史太阳辐射总量；随后结合基于晴空指数、太阳高度角与日照时数的光合有效辐射估算模型，最终得到1961年至2014年间全国724个常规气象站的逐日历史光合有效辐射数据集。