• COVID-19 cases in the tropical regions were relatively lower than the European & American regions. • Observed a substantial reduction in NO 2 , low reduction in CO, and low to moderate reduction in AOD • High COVID-19 hazard (AH: 4 to 9 g m −3) in major of the globe during April-July 2020 • Northern Hemisphere may be more susceptible compared to tropical regions in May-July 2020. • Tropical regions may be comparatively more prone to outbreaks in October-November 2020.

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The magnitude 7.8 Gorkha earthquake in April 2015 ruptured a 150-km-long section of the Himalayan décollement terminating close to Kathmandu 1-4 . The earthquake failed to rupture the surface Himalayan frontal thrusts and raised concern that a future M w ≤ 7.3 earthquake could break the unruptured region to the south and west of Kathmandu. Here we use GPS records of surface motions to show that no aseismic slip occurred on the ruptured fault plane in the six months immediately following the earthquake. We find that although 70 mm of afterslip occurred locally north of the rupture, fewer than 25 mm of afterslip occurred in a narrow zone to the south. Rapid initial afterslip north of the rupture was largely complete in six months, releasing aseismic-moment equivalent to a M w 7.1 earthquake. Historical earthquakes in 1803, 1833, 1905 and 1947 also failed to rupture the Himalayan frontal faults, and were not followed by large earthquakes to their south. This implies that significant relict heterogeneous strain prevails throughout the Main Himalayan Thrust. The considerable slip during great Himalayan earthquakes may be due in part to great earthquakes tapping reservoirs of residual strain inherited from former partial ruptures of the Main Himalayan Thrust.The spatial distribution of surface deformation in the April M w 7.8 Nepal earthquake and its M w 7.3 aftershock ten days later was captured by several InSAR scenes and by continuously operating GPS receivers 1-8 . These data indicate that an average slip of 3.5 m occurred on a 60-km-wide × 150-km-long rupture of the northdipping décollement, the Main Himalayan Thrust (MHT), with maximum slip locally reaching 7 m approximately 15 km north of Kathmandu. Rupture propagated eastwards along the region of maximum interseismic strain near the Greater Himalaya, but terminated to the south near the Kathmandu valley (Fig. 1).The interseismic convergence rate in Nepal observed geodetically 9,10 is 18-20 mm yr −1 , similar to the rate of advance of the Himalaya over the Indian plate inferred from geological evidence 11 . The Indian plate descends beneath Tibet aseismically north of a seismically active transition zone in northern Nepal, south of which three decades of geodetic data indicate that the MHT is effectively locked 12 . The occasional rupture of this locked décollement accommodates the incremental northward passage of the Indian plate beneath the Himalaya. A several-thousand year record of this slip is emerging from the exhumation of surface ruptures of Himalayan frontal faults 13-15 (Main Frontal Thrust, MFT); however, the 2015 earthquake is one of several M ≤ 7.8Himalayan earthquakes whose southward rupture failed to rupture the MFT, and whose contribution to facilitating Himalayan moment release thereby eludes palaeoseismic investigation.InSAR data reveal that the 2015 earthquake did, however, trigger ∼5 cm of near-surface slip on a subsidiary branch of the frontal fault, the Main Dun Thrust (MDT), with no significant coseismic slip on the décollement between the...

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Identification of invasion hotspots that support multiple invasive alien species (IAS) is a pre-requisite for control and management of invasion. However, till recently it remained a methodological challenge to precisely determine such invasive hotspots. We identified the hotspots of alien species invasion in India through Ecological Niche Modelling (ENM) using species occurrence data from the Global Biodiversity Information Facility (GBIF). The predicted area of invasion for selected species were classified into 4 categories based on number of model agreements for a region i.e. high, medium, low and very low. About 49% of the total geographical area of India was predicted to be prone to invasion at moderate to high levels of climatic suitability. The intersection of anthropogenic biomes and ecoregions with the regions of 'high' climatic suitability was classified as hotspot of alien plant invasion. Nineteen of 47 ecoregions of India, harboured such hotspots. Most ecologically sensitive regions of India, including the 'biodiversity hotspots' and coastal regions coincide with invasion hotspots, indicating their vulnerability to alien plant invasion. Besides demonstrating the usefulness of ENM and open source data for IAS management, the present study provides a knowledge base for guiding the formulation of an effective policy and management strategy for controlling the invasive alien species.