Publications by Abolfazl Irani Rahaghi

Combined Earth observations reveal the sequence of conditions leading to a large algal bloom in Lake Geneva

Damien Bouffard, Abolfazl Irani Rahaghi, Marco Toffolon, Oscar Rodrigo Sepúlveda Steiner, Rafael Sebastian Reiss, Frédéric Charles Soulignac

Freshwater algae exhibit complex dynamics, particularly in meso-oligotrophic lakes with sudden and dramatic increases in algal biomass following long periods of low background concentration. While the fundamental prerequisites for algal blooms, namely ligh ...

Springernature2024

A low-cost, autonomous mobile platform for limnological investigations, supported by high-resolution mesoscale airborne imagery

Ulrich Lemmin, David Andrew Barry, Anton Ivanov, Htet Kyi Wynn, Jérôme Béguin, Ludovic Zulliger, Nawaaz Sidharth Gujja Shaik, Jean-Luc Liardon, Philippe Olivier Paccaud, Beat Marcel Geissmann, Abolfazl Irani Rahaghi, Pascal Klaus, Stepan Tulyakov

Two complementary measurement systems – built upon an autonomous floating craft and a tethered balloon – for lake research and monitoring are presented. The autonomous vehicle was assembled on a catamaran for stability, and is capable of handling a variety ...

2019

Surface Water Temperature Heterogeneity at Subpixel Satellite Scales and Its Effect on the Surface Cooling Estimates of a Large Lake: Airborne Remote Sensing Results From Lake Geneva

Ulrich Lemmin, David Andrew Barry, Abolfazl Irani Rahaghi

The dynamics of spatial heterogeneity of lake surface water temperature (LSWT) at subpixel satellite scale O(1 m) and its effect on the surface cooling estimation at typical satellite pixel areas O(1 km2) were investigated using an airborne platform. The m ...

2019

Achieving high-resolution thermal imagery in low-contrast lake surface waters by aerial remote sensing and image registration

Ulrich Lemmin, Daniel Sage, David Andrew Barry, Abolfazl Irani Rahaghi

A two-platform measurement system for realizing airborne thermography of the Lake Surface Water Temperature (LSWT) with ~0.8 m pixel resolution (sub-pixel satellite scale) is presented. It consists of a tethered Balloon Launched Imaging and Monitoring Plat ...

2019

The Importance of Systematic Spatial Variability in the Surface Heat Flux of a Large Lake: A Multiannual Analysis for Lake Geneva

Ulrich Lemmin, David Andrew Barry, Abolfazl Irani Rahaghi, Andrea Cimatoribus

The spatiotemporal surface heat flux (SurHF) distribution over Lake Geneva, the largest lake in Western Europe, was estimated for a 7‐year period (2008–2014). Data sources included hourly maps of over‐the‐lake assimilated meteorological data from a validat ...

American Geophysical Union2019

Improving surface heat flux estimation for a large lake through model optimization and two-point calibration: The case of Lake Geneva

Ulrich Lemmin, Damien Bouffard, David Andrew Barry, Abolfazl Irani Rahaghi, Andrea Cimatoribus

Net Surface Heat Flux (SurHF) was estimated from 2008 to 2014 for Lake Geneva (Switzerland/France), using long‐term temperature depth profiles at two locations, hourly maps of reanalysis meteorological data from a numerical weather model and lake surface w ...

Association for the Sciences of Limnology and Oceanography (ASLO)2018

Large-scale and meso-scale surface heat flux patterns of Lake Geneva

Abolfazl Irani Rahaghi

Diverse studies have confirmed the adverse impact of global climate change in lakes. In order to establish effective water quality management policies, it is essential to understand how the heat exchange between the atmosphere and the lake evolves under th ...

EPFL2018