The increasing methane emissions from the upstream oil and gas sector deviates from the goals of the Paris Agreement on sustainable development and climate control. This paper reviews recent direct measurement results and technological advances in the upstream oil and gas sector, based on more than 100 sources published between 2018 and 2022. No consensus was found on the correlation between methane emissions and well data items such as production volume and well age. Aircraft surveys were the most frequently used technology during the study period. Developed countries lead in direct measurement, with only 12.5% of studies conducted in developing countries. The sensing method and the performance of sensor carriers lead to different characterisations of direct measurement techniques. Growing upstream methane emissions accelerate global warming and pose risks to groundwater. Mitigating super-emitters and reported venting and flares could reduce total methane emissions by 20% and 25%, respectively. China, the world's largest methane emitter, emitted approximately 2135 kt methane from its upstream oil and gas sector, mainly through venting (80%). Direct methane measurements and the strength of government management could assist China in prioritising carbon emission reduction and filling the legislative gap.