Prior to academic pursuits, Holst was a military radar operator who participated in NATO KFOR in 2008. His studies in meteorology in Leibniz University Hannover led to a BSc in meteorology in 2012. Thematically the thesis in the radiative transfer research group revolved around measuring UV penetration of various fabric samples in the laboratory. In 2009, he participated in a research internship on windshear analysis and prediction for aviation at the Hong Kong Observatory with Mark Wenig and P. W. Chan. During his PhD at City University of Hong Kong, he numerically investigated the behaviour of heavy precipitation amplification by urban processes with WRF. After his PhD in 2017 he moved to KIT, to contribute to urban Doppler lidar measurements for PALM-4U model evaluation as part of the Urban Climate under Change consortium. From 2019 to 2022, he led the second phase of the project focusing on microscale model evaluation using ground based remote sensing data. Since 2022, he leads the Urban- and Eco-Climatology research group in addition to his project contributions to the ICOS Cities H2020 consortium.

Holst has contributed to technical reports on PALM-4U evaluation, as well as Doppler lidar measurement methodology, a book chapter on urban climate perspectives on smart city concepts. He presented, contributed and published on the topics of multiscale modelling and observation for urban context. City University of Hong Kong awarded him with “The Outstanding Academic Performance Award for Research Degree Students” and “Certificate of Merit for good performance in Teaching Students: First Steps” and selected him as the university envoy for the Global Young Scientists Summit 2016.