Seamless Modelling for Environmental Studies: Enviro-HIRLAM Recent Research and Development&#160;
Authors: Mahura Alexander , Nuterman Roman , Baklanov Alexander , Nerobelov Georgii , Savenets Mykhailo , Pysarenko Larysa , Sedeeva Margarita , Amosov Pavel , Losev Aleksandr , Maksimova Victoria , Pankratov Fidel , Krakowska Svitlana , Smyshlayaev Sergey , Petaja Tuukka , Kulmala Markku 
Published: March 2022

&lt;p&gt;The &lt;strong&gt;Enviro-HIRLAM&lt;/strong&gt; (Environment - HIgh Resolution Limited Area Model) is seamless/ online integrated numerical weather prediction and atmospheric chemical transport modelling system capable to simulate simultaneously meteorology &amp;#8211; atmospheric composition on regional to subregional &amp;#8211; urban scales.&lt;/p&gt;&lt;p&gt;The &lt;strong&gt;main areas&lt;/strong&gt; of the model research and development include: downscaling/&amp;#160; nesting&amp;#160; for&amp;#160; high&amp;#160; resolutions;&amp;#160; improved&amp;#160; resolving&amp;#160; boundary&amp;#160; and&amp;#160; surface&amp;#160; layers&amp;#160; structures; urbanization and sub-layer processes; improvement of advection schemes; integration of natural and anthropogenic emission inventories; implementation of gas-phase chemistry mechanisms, aerosol dynamics and microphysics, aerosol feedback and interactions mechanisms.&lt;/p&gt;&lt;p&gt;The &lt;strong&gt;Enviro-components&lt;/strong&gt; includes: gas-phase chemistry; aerosol microphysics with nucleation, coagulation, condensation of sulfate, mineral dust, sea-salt, black and organic carbon together&amp;#160; with&amp;#160; aerosols&amp;#8217; dry and wet deposition, sedimentation processes; &amp;#160;parameterisations of urban sublayer with modifications of the interaction soil&amp;#8211;biosphere&amp;#8211;atmosphere scheme; sulfur cycle mechanism with dimethyl sulfide, sulfur dioxide and sulfate; radiation scheme improved to&amp;#160; account&amp;#160; explicitly&amp;#160; for&amp;#160; aerosol&amp;#160; radiation interactions&amp;#160; for&amp;#160; &amp;#160;aerosol&amp;#160; subtypes; aerosol&amp;#160; activation&amp;#160; implemented in condensation-convection scheme with nucleation dependent on aerosol properties and ice-phase processes; locally&amp;#160; mass-conserving&amp;#160; semi-Lagrangian&amp;#160; numerical&amp;#160; advection&amp;#160; scheme; natural and anthropogenic emission inventories.&lt;/p&gt;&lt;p&gt;The Enviro-HIRLAM utilises extraction and pre-processing of initial/ boundary meteorology-chemistry-aerosol conditions and observations for data assimilation (from ECMWF&amp;#8217;s ERA-5 &amp; CAMS), pre-processing of selected emission inventories for anthropogenic and natural emissions. The latest version has been run on CRAY-XC30/40 and Atos BullSequana HPCs machines, and it has been developed through the research and HPC projects such as Enviro-HIRLAM at CSC and Enviro-PEEX &amp; Enviro-PEEX(Plus) at ECMWF, as well as other research projects.&lt;/p&gt;&lt;p&gt;The &lt;strong&gt;research, development and science education of the modelling system and its applications&lt;/strong&gt; will be demonstrated on examples, where the Enviro-HIRLAM is used as a research tool&amp;#160; for studies in domain of the Pan-Eurasian Experiment (PEEX; https://www.atm.helsinki.fi/peex) programme. Examples of such include: aspects of regional-subregional-urban downscaling with focus on metropolitan areas of St.Petersburg and Moscow; influence of dust transport from artificial tailing dumps and Cu-Ni smelters of the Kola Peninsula on pollution of environment and health of population; aerosol feedbacks and interactions at regional scale in the Arctic-boreal domain; evaluation of atmosphere-land-sea surfaces interactions, and in particular, heat-moisture exchange/ regime between these surfaces and for better understanding and forecasting of local meteorology in the Arctic; analysis of urban meteorology and atmospheric pollution with integrated approach to high-resolution numerical modelling; and others. The modelling output provides meteorology-chemistry related input to assessment studies for population and environment as well as can be integrated into GIS environment for further risk/vulnerability/consequences/etc. estimation, and other studies.&lt;/p&gt;&lt;p&gt;The &lt;strong&gt;science education component&lt;/strong&gt; for the model is also realised though short-term visits of young researchers, organization and carrying out research training weeks. The latest face-to-face trainings took place in Apr and Jun 2019 (Helsinki and Tyumen), and online in Nov-Dec 2021 (https://megapolis2021.ru).&lt;/p&gt;