Tiangang Yin

Tiangang Yin
NASA Goddard Space Flight Center / University of Maryland

PhD

About

63
Publications
19,445
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,059
Citations
Citations since 2016
51 Research Items
1019 Citations
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250
Additional affiliations
January 2018 - present
University of Maryland / NASA Goddard Space Flight center
Position
  • Researcher
Education
November 2011 - May 2015
University of Toulouse
Field of study
  • Geosciences, Astrophysics & Space Sciences
January 2009 - June 2011
National University of Singapore
Field of study
  • Electrical and Computer Engineering
August 2004 - May 2008

Publications

Publications (63)
Article
Light Detection And Ranging (LiDAR) devices are increasingly used to provide data on Earth’s landscapes structures and atmosphere constituents. Their developments, especially with scanning and multi-beam systems require accurate modeling tools to analyze existing data and to design future systems. A few radiative transfer models (RTMs) can simulate...
Article
Comparison of actual and simulated remotely sensed data is difficult since simulated data are not realistic in terms of both radiometry and geometry. This paper presents a modeling approach that considers the multi-directional acquisition within sensor field of view (FOV) in order to simulate realistic images of Earth surfaces, as acquired by passi...
Article
In radiative transfer modeling, the angular variable Ω discretization can strongly influence the radiative transfer simulation, especially with small numbers of discrete directions. Most radiative transfer models use discrete ordinate method or finite volume method for solving the transport equation. Both of the methods have their own algorithms to...
Article
Satellite and airborne optical sensors are increasingly used by scientists, and policy makers, and managers for studying and managing forests, agriculture crops, and urban areas. Their data acquired with given instrumental specifications (spectral resolution, viewing direction, sensor field-of-view, etc.) and for a specific experimental configurati...
Preprint
Heat released from the energy consumption in buildings (QB) is an important component of anthropogenic heat, which is a major contribution to the urban heat island (UHI) phenomenon. However, it is still a challenge to integrate all the available data to improve the estimation of QB due to inconsistencies among multiple data sources. This paper pres...
Article
Full-text available
Recent advances in instruments and retrieval methods enable measurements of solar-induced chlorophyll fluorescence (SIF) across a wide range of scales. Radiative transfer (RT) models for simulating scattering and (re-)absorption of SIF provide a powerful tool to study the upscaling of SIF signal from leaf level to terrestrial ecosystems. Based on t...
Preprint
Full-text available
Light Detection And Ranging (LiDAR) is a developed technology that has been widely used to measure the Earth's surface by acquiring accurate three-dimensional (3D) information. LiDAR radiative transfer (RT) models provide physical-based simulation tools for interpreting LiDAR signal and estimating surface characteristics by model inversion. DART (D...
Article
Full-text available
Light Detection And Ranging (LiDAR) remote sensing is increasingly needed to assess the 3D architecture of Earth's surface. Physically-based LiDAR radiative transfer (RT) models are essential tools for interpreting LiDAR signals, designing LiDAR systems, and validating information retrieval methods. Discrete Anisotropic Radiative Transfer (DART) is...
Article
Full-text available
Current thermal infrared satellite images are full of mixed pixels. This work is a quantitative analysis, based on radiative transfer modelling, of the distribution of mixed pixels and their impact on the use of TES. TES was applied to radiance images of the cities of Basel and Heraklion simulated at different spatial resolutions by the DART radiat...
Article
Airborne laser scanning (ALS) has been widely used to map gap probability and leaf area index (LAI) distribution at plot and landscape scales. As an indirect measurement, most ALS methods to estimate LAI combine waveform or point density information with supporting field measurements such as the leaf angle distribution, gap probability, or direct L...
Article
Although remote sensing (RS) of solar-induced chlorophyll fluorescence (SIF) is increasingly used as a valuable source of information about vegetation photosynthetic activity, the RS SIF observations are significantly influenced by canopy-specific structural features (i.e., canopy architecture including leaf area index and presence of woody compone...
Article
Solar-induced fluorescence (SIF) is a subtle but informative optical signal of vegetation photosynthesis. Remotely sensed SIF integrates environmental, physiological and structural changes that alter photosynthesis at leaf, plant and canopy scales. Radiative transfer models are ideally suited to investigate the complex sources of variability in the...
Article
Full-text available
DART calibration is an iterative inversion method that is applied to shortwave (SW) satellite images to get maps of spectral signatures (SS) of city materials at the satellite spatial resolution. Therefore, it is potentially a handy spectral unmixing tool. However, up to now, it has only been validated by comparing the time series of SW radiative b...
Article
Full-text available
The microclimatic conditions of the urban environment influence significantly the thermal comfort of human beings. One of the main human biometeorology parameters of thermal comfort is the Mean Radiant Temperature (Tmrt), which quantifies effective radiative flux reaching a human body. Simulation tools have proven useful to analyze the radiative be...
Article
Full-text available
Saturation effects limit the application of vegetation indices (VIs) in dense vegetation areas. The possibility to mitigate them by adopting a negative soil adjustment factor X is addressed. Two leaf area index (LAI) data sets are analyzed using the Google Earth Engine (GEE) for validation. The first one is derived from observations of MODerate res...
Article
Full-text available
The fraction of absorbed photosynthetically active radiation (fAPAR) is a key parameter for estimating the gross primary production (GPP) of trees. For continuous, dense forest canopies, fAPAR, is often equated with the intercepted fraction, fIPAR. This assumption is not valid for individual trees in urban environments or parkland settings where th...
Article
Full-text available
In response to the comment on our paper "High-resolution, multi-layer modelling of Singapore's urban climate incorporating local climate zones", we provide detailed response to each of the incorrect accusations with scientifically based evidence. We have evaluated our model using all the available observational data, and the results showed good agr...
Conference Paper
Remote sensing (RS) dedicated to the study of land surfaces benefits from more and more advanced sensors. However, the interpretation of RS data is often is often inaccurate due to the complexity of the observed land surfaces. Therefore, RS models, in particular physical models, that simulate RS observations of the three-dimensional (3D) landscapes...
Article
Field measurements of leaf area density (LAD) and leaf area index (LAI) for individual trees have increased in importance and relevance with the advent of high spatial resolution remote sensing for the urban landscape. However, indirect field measurements of LAD/LAI for widely dispersed individual trees have not been comprehensively evaluated. The...
Article
Full-text available
Radiative transfer models (RTMs) of vegetation canopies can be applied for the retrieval of numerical values of vegetation properties from satellite data. For such retrieval, it is necessary first to apply atmospheric correction to translate the top-of-atmosphere (TOA) satellite data into top-of-canopy (TOC) values. This atmospheric correction typi...
Article
Methods to retrieve urban surface temperature (Ts) from remote sensing observations with sub-building scale resolution are developed using the Discrete Anisotropic Radiative Transfer (DART, Gastellu-Etchegorry et al., 2012) model. Corrections account for the emission and absorption of radiation by air between the surface and instrument (atmospheric...
Article
Full-text available
Airborne lidar point clouds of vegetation capture the 3-D distribution of its scattering elements, including leaves, branches, and ground features. Assessing the contribution from vegetation to the lidar point clouds requires an understanding of the physical interactions between the emitted laser pulses and their targets. Most of the current method...
Article
Full-text available
Three-dimensional (3D) radiative transfer models are the most accurate remote sensing models. However, presently the application of 3D models to heterogeneous Earth scenes is a computationally intensive task. A common approach to reduce computation time is abstracting the landscape elements into simpler geometries (e.g., ellipsoid), which, however,...
Article
Full-text available
Increased urbanization and climate change have resulted in the intensification of the urban heat island (UHI) effect, particularly in tropical cities. One of the main causes of UHI is the man-made urban surfaces influencing the radiation budget by absorbing, reflecting, and emitting radiation at various wavelengths. The radiative budget of a city i...
Article
Full-text available
Key Points: • Developing local climate zone map using various remote sensing data for incorporating into WRF to simulate UHI. • Evaluating the capability of WRF/multilayer urban canopy model in reproducing Singapore's urban climate. • Investigating the impacts of anthropogenic heat and sea breeze on Singapore's UHI and local circulations. Abst...
Article
The anisotropic scattering behavior of land surface is characterized by its bidirectional reflectance-distribution function (BRDF). However, a physically consistent BRDF definition is still lacking for heterogeneous and rugged terrain that accounts for approximately 24% of Earth's land surface. In this study, we revisited current BRDF definitions a...
Article
Full-text available
Three-dimensional (3D) radiative transfer modeling of the transport and interaction of radiation through earth surfaces is challenging due to the complexity of the landscapes as well as the intensive computational cost of 3D radiative transfer simulations. To reduce computation time, current models work with schematic landscapes or with small-scale...
Preprint
Full-text available
Abstract We applied Weather Research and Forecasting (WRF) model’s Multilayer Urban Canopy Model (MLUCM), including Building Effect Parameterization and Building Energy Model (BEP-BEM) schemes, to simulate the urban climate of Singapore during April 2016, when a series of heat wave events occurred. The absence of high-resolution urban landscape da...
Article
Topographic effects on canopy reflectance play a pivotal role in the retrieval of surface biophysical variables over rugged terrain. In this paper, we proposed a new canopy anisotropic reflectance model for discrete forests, Geometric Optical and Mutual Shadowing and Scattering-from-Arbitrarily-Inclined-Leaves model coupled with Topography (GOSAILT...
Article
Full-text available
Urban geometry and materials combine to create complex spatial, temporal and directional patterns of longwave infrared (LWIR) radiation. Effective anisotropy (or directional variability) of thermal radiance causes remote sensing (RS) derived urban surface temperatures to vary with RS view angles. Here a new and novel method to resolve effective the...
Conference Paper
Full-text available
The advantage of using remote sensing data in urban climatology study is to obtain simultaneous synoptic view of the full urban surface. Remotely-sensed data can be utilized to derive important parameters for numerical models to improve model's prediction accuracy. One such example is the local climate zone (LCZ) proposed by Stewart and Oke (2012),...
Article
A semi-empirical multilayer urban canopy model is developed to estimate the vertical dispersion of traffic emissions in high density urban areas. It is motivated by the heterogeneity of urban morphology in real urban cities and the need of quick urban design and planning. The urban canopy is divided into multiple layers, to include the impact of bu...
Article
Canopy radiation and scattering signals contain abundant vegetation information. Many biophysical parameters can be quantitatively retrieved with the help of canopy radiation and scattering models. Joint simulation of three-dimensional (3-D) models for multiband that combines the advantages of different spectral (frequency) domains could be a usefu...
Article
To better understand the life-essential cycles and processes of our planet and to further develop remote sensing (RS) technology, there is an increasing need for models that simulate the radiative budget (RB) and RS acquisitions of urban and natural landscapes using physical approaches and considering the three-dimensional (3-D) architecture of Ear...
Article
The 3D distribution of plant material is a key parameter to describe vegetation structure, which influences several processes such as radiation interception and ecosystem functioning. Vegetation covers are often described using Leaf Area Index (LAI) or Plant Area Index (PAI) for monitoring or modeling purposes. Characterizing vegetation 3D structur...
Chapter
Full-text available
Need for better understanding and more accurate estimation of radiative fluxes in urban environments, specifically urban surface albedo and exitance, motivates development of new remote sensing and three‐dimensional (3D) radiative transfer (RT) modeling methods. The discrete anisotropic radiative transfer (DART) model, one of the most comprehensive...
Conference Paper
The need of better accuracy for analyzing remote sensing (RS) data of complex Earth surfaces explains the increasing need of models that simulate RS data with physical approaches. Similarly, the study of Earth surfaces functioning requires physical models that simulate the 3D radiative budget (RB) of these surfaces. DART (Discrete Anisotropic Radia...
Conference Paper
The need of better accuracy to analyze remote sensing (RS) data and radiative budget (RB) of Earth surfaces explains the demand of physical models of RS and RB data. DART (Discrete Anisotropic Radiative Transfer) model is probably the most comprehensive three-dimensional (3D) physical model. Indeed, with original ray tracking and Monte Carlo method...
Article
Full-text available
Sentinel-2 (S2) earth observation satellite mission, launched in 2015, is foreseen to promote within-field decisions in Precision Agriculture (PA) for both: (1) optimizing crop production; and (2) regulating environmental impacts. In this second scope, a set of Leaf Area Index (LAI) derived from S2 type time-series (2006-2010, using Formosat-2 sate...
Conference Paper
Full-text available
In the frame of the H2020 project, URBANFLUXES (http://urbanfluxes.eu/), new modeling is developed to improve the efficiency of the study of urban canopies with remote sensing, with the modeling of satellite and in- situ acquisitions (reflectance, albedo, brightness temperature), and also 3D radiative and energy budgets. The 3D radiative transfer m...
Conference Paper
Full-text available
Physically-based radiative transfer modeling is the key to remote sensing of forest ecosystems. To scale spectral information from the leaf to the sensor level, the canopy architecture of a forest, illumination conditions and the viewing geometry have to be taken into account. Therefore, a new airborne image simulation approach is being developed f...
Conference Paper
DART model was extended for simulating satellite Lidar data of 3D Earth scenes with Monte Carlo based methods. 2 major modeling methods were developed. (1) Monte Carlo method for efficiently handling complex phase functions: once scattering directions with close occurrence probabilities are grouped within classes, a 1st random pulling gives the cla...
Conference Paper
Full-text available
Nowadays, several optical space-borne systems with high resolution, high temporal revisit frequency and constant viewing angles are preparing to be be launched: Venμs, Sentinel-2, etc. The usefulness of these data will be limited due to for instance cloud coverage over the scene. Image fusion techniques with other satellite products of even higher...
Conference Paper
A DART based data processing chain was developed for assessing the potential of a high spatial resolution geostationary satellite. It simulates time series of TOA and BOA radiance values and their spatial variability at any satellite spatial resolution, for any experimental, instrumental and view configuration (e.g., geosynchronous orbit). Account...
Conference Paper
Many radiative transfer (RT) models combine exact kernel and discrete ordinate techniques for solving the transport equation. They discretize the 4π space into a finite number of angular sectors, with directions along which radiation propagates. They can be more or fewer and equally spaced or not. RT model improvement is usually focused on 3D lands...
Conference Paper
Full-text available
Lusi is a mud volcano in East Java, Indonesia, which started its eruption on 29th May 2006 and never stopped. To study this volcano, we used SAR interferometry with ALOS/Palsar satellite images from 2006 to 2010. By creation of a set of interferograms, and suppression of unwanted components, such as Earth curvature and elevation, we were able to co...
Conference Paper
Full-text available
On September 30th, 2009, a major earthquake of magnitude 7.6 occurred near the west coast of Sumatra close to the city of Padang. On October 1st a significant aftershock (magnitude 6.6) occurred 270 km away. The casualties are estimated at 1200. This earthquake comes at a time when seismic activity in the region is particularly high. The purpose of...