###### Abstract
The remaining studies have mainly focused on how climate and factors such as slope and elevation affect vegetation productivity at small scales [22; 23]. There is still a lack of regional characterization of climate impacts on grassland productivity, which limits our insights into climate-vegetation mechanisms in specific environments. In addition, it is not yet unanimously recognized whether the positive or negative influence of climatic factors on NPP depends on spatial location. For example, field control experiments have shown that the effect of temperature on NPP is negatively correlated with elevation, whereas regional remote sensing methods have come to the opposite conclusion [6; 24]. It confounds our understanding of vegetation-climate processes, and more researches are needed to address this issue. NPP sensitivity is another variable that deserves consideration in understanding the relationship between vegetation and climate. It reflects the extent to which NPP responds to changes in temperature and precipitation, and is a characteristic that determines the stability of vegetation in response to climatic disturbances [25]. Vegetation type and elevation are both important influences that alter the NPP sensitivity to climate. For example, a study of North American drylands found that human disturbance caused up to a fivefold increase in the sensitivity of NPP to interannual variation in precipitation [26], and another study in the Qilian Mountains of China revealed a decrease in the NPP sensitivity to temperature with increasing elevation in an alpine desert [6]. Most of the existing studies examined the effects of individual factors on NPP sensitivity, ignoring the combined effects of multiple factors. There is a need to explore the processes by which multiple factors combine to influence vegetation productivity. The Tibetan Plateau (TP) occupies nearly one quarter of China's land area and possesses one third of China's grassland. With less human activity and stronger climate change in recent years than other regions [27], the TP has become an ideal area in which to study the response of grass growth to climate change. Different scholars have carried out NPP studies on the TP grassland from multiple perspectives, but the results are still subject to uncertainty due to the inconsistencies in study duration, data sources and analysis methods [28; 29]. Findings such as the effect of temperature or precipitation on NPP increasing or decreasing with elevation have been reported [6; 19; 30]. However, the conclusions of these studies were simply determined by partial correlation coefficients, ignoring the combined effects of temperature and precipitation on vegetation. Moreover, these studies did not take into account spatial patterns in the explanatory capacity of temperature and precipitation for NPP, nor in latitudinal differences in the sensitivity of NPP to changes in temperature and precipitation. In order to clarify these knowledge gaps, this study took the TP alpine grassland as the research object and used spatial analysis methods to reveal the effects of the climatic factors of temperature and precipitation on the variation of NPP with elevation. Specifically, we aimed to (1) reveal the spatial and temporal patterns of NPP variation in TP grassland during 2001-2022, (2) explore the elevational patterns of the temperature and precipitation effects on NPP, and (3) illustrate whether elevation affects the sensitivity of NPP to temperature and precipitation.