DELFI: Deep Mixture Models for Long-term Air Quality Forecasting in the Delhi National Capital Region

Naishadh Parmar; Raunak Shah; Tushar Goswamy; Vatsalya Tandon; Ravi Sahu; Ronak Sutaria; Purushottam Kar; Sachchida Nand Tripathi

arXiv · 2210.15923

DELFI: Deep Mixture Models for Long-term Air Quality Forecasting in the Delhi National Capital Region

Naishadh Parmar·Raunak Shah·Tushar Goswamy·Vatsalya Tandon·Ravi Sahu·Ronak Sutaria·Purushottam Kar·Sachchida Nand Tripathi

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Abstract

The identification and control of human factors in climate change is a rapidly growing concern and robust, real-time air-quality monitoring and forecasting plays a critical role in allowing effective policy formulation and implementation. This paper presents DELFI, a novel deep learning-based mixture model to make effective long-term predictions of Particulate Matter (PM) 2.5 concentrations. A key novelty in DELFI is its multi-scale approach to the forecasting problem. The observation that point predictions are more suitable in the short-term and probabilistic predictions in the long-term allows accurate predictions to be made as much as 24 hours in advance. DELFI incorporates meteorological data as well as pollutant-based features to ensure a robust model that is divided into two parts: (i) a stack of three Long Short-Term Memory (LSTM) networks that perform differential modelling of the same window of past data, and (ii) a fully-connected layer enabling attention to each of the components. Experimental evaluation based on deployment of 13 stations in the Delhi National Capital Region (Delhi-NCR) in India establishes that DELFI offers far superior predictions especially in the long-term as compared to even non-parametric baselines. The Delhi-NCR recorded the 3rd highest PM levels amongst 39 mega-cities across the world during 2011-2015 and DELFI's performance establishes it as a potential tool for effective long-term forecasting of PM levels to enable public health management and environment protection.

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Naishadh Parmar, Raunak Shah, Tushar Goswamy, Vatsalya Tandon, Ravi Sahu, Ronak Sutaria, Purushottam Kar, Sachchida Nand Tripathi. 2022-10-28. DELFI: Deep Mixture Models for Long-term Air Quality Forecasting in the Delhi National Capital Region. https://arxiv.org/abs/2210.15923

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