This study describes the scientific basis for a public web page that gives access to a large set of climate model simulations. This web page is called the Monash Simple Climate Model. It provides access to more than 1300 experiments and has an interactive interface for fast analysis of the experiments and open access to the data. The study gives a short overview of the simulation experiments and discusses some of the results.

The development of atmospheric and oceanic models in spherical coordinates requires a quantitative assessment of the accuracy of the models’ simulations. Such an assessment tool is developed here based on analytic wave solutions of the linearized shallow-water equations. New error measures are employed which are more relevant then formerly employed error measures for the single-mode simulations used in the proposed test case. Code is supplied for calculating the required initial fields.

We present the first representation of grass pollen in a 3-D dispersion model in Australia, tested using observations from eight counting sites in Victoria. The technology was developed in response to the severe thunderstorm asthma event which took place in Melbourne in November 2016. A total of 10 pollen emission methodologies were developed and evaluated. The best results were obtained using statistical methods that included elements of the satellite derived enhanced vegetation index.

Photosynthesis and evapotranspiration are processes with global significance for climate, carbon and water cycling. Process-orientated simulation of these processes and their interactions have till now come at high computational cost. Here we present a new coupled model of intermediate complexity operating at orders of magnitude greater speed. Independent evaluation at FLUXNET sites for a single, global parameterization shows good agreement, with a typical R² value of ~ 0.60.

The melting at the base of floating ice shelves is the main driver of the Antarctic ice sheet current retreat. Here, we use an ideal set-up to assess a wide range of melting parameterisations depending on oceanic properties with regard to a new ocean–ice-sheet coupled model, published here for the first time. A parameterisation that depends quadratically on thermal forcing in both a local and a non-local way yields the best results and needs to be further assessed with more realistic set-ups.

DECIPHeR (Dynamic fluxEs and ConnectIvity for Predictions of Hydrology) is a new modelling framework that can be applied from small catchment to continental scales for complex river basins. This paper describes the modelling framework and its key components and demonstrates the model’s ability to be applied across a large model domain. This work highlights the potential for catchment- to continental-scale predictions of streamflow to support robust environmental management and policy decisions.

A new oxidation mechanism for biogenic volatile organic compounds is presented and implemented in the large-scale chemistry transport model MAGRITTE. The mechanism accounts for all major recent advances regarding isoprene oxidation. Evaluation against airborne measurements over the US demonstrates a good overall agreement. The mechanism incorporates newly-proposed pathways for formic and acetic acid formation, representing ~ 20 % of their global identified source.

In the real world the atmosphere, oceans and land surface are closely interconnected, and yet the prediction systems used for weather and ocean forecasting tend to treat them in isolation. This paper describes the third version of a regional modelling system which aims to represent the feedback processes between sky, sea and land. The main innovation introduced in this version enables waves to affect the underlying ocean. Coupled results from four different month-long simulations are analysed.

G³M is a new global groundwater model (http://globalgroundwatermodel.org) that simulates lateral and vertical flows as well as exchanges with surface water bodies like rivers, lakes, and wetlands for the whole globe except Antarctica and Greenland. The newly developed model framework enables an efficient integration into established global hydrological models. This paper presents the G³M concept and specific model design decisions together with first results under a naturalized equilibrium.

Tillage practices are under-represented in global biogeochemical models so that assessments of agricultural greenhouse gas emissions and climate mitigation options are hampered. We describe the implementation of tillage modules into the model LPJmL5.0, including multiple feedbacks between soil water, nitrogen, and productivity. By comparing simulation results with observational data, we show that the model can reproduce reported tillage effects on carbon and water dynamics and crop yields.

CLaMS is a Lagrangian transport model suitable for simulating atmospheric transport and chemistry. The novel approach of CLaMS is its description of atmospheric mixing. Whereas the common approach is to minimize the numerical diffusion ever present in the modeling of transport, CLaMS is a first attempt to apply this undesirable disturbing effect to parametrize the true physical mixing. In this paper, we show how this concept works both in the stratosphere and in the troposphere.

Computer models are used to predict river flows. A good model should represent the river basin to which it is applied so that flow predictions are as realistic as possible. However, many different computer models exist, and selecting the most appropriate model for a given river basin is not always easy. This study combines computer code for 46 different hydrological models into a single coding framework so that models can be compared in an objective way and we can learn about model differences.

To provide reliable projections of the ice-sheet contribution to future sea-level rise, ice sheet models must be able to simulate the observed ice sheet present-day state. Using a low computational iterative minimisation procedure, based on the adjustment of the basal drag coefficient, we rapidly minimise the errors between the simulated and the observed Greenland ice thickness and ice velocity, and we succeed in stabilising the simulated Greenland ice sheet state under present-day conditions.

We present a model that aggregates simulated runoff along a river (i.e. a routing model). The unique feature of the model is that it can be run at multiple resolutions without any modifications to the input data. The model internally (dis-)aggregates all input data to the resolution given by the user. The model performance does not depend on the chosen resolution. This allows efficient model calibration at coarse resolution and subsequent model application at fine resolution.

To study turbulence in heterogeneous terrain, high-resolution LES is desired. However, the desired resolution is often restricted by computational constraints. We present a two-way interactive vertical grid nesting technique that enables high-resolution LES of the surface layer. By employing a finer grid only close to the surface layer, the total computational memory requirement is reduced. We demonstrate the accuracy and performance of the method for a convective boundary layer simulation.

This study develops the representation of secondary organic aerosol (SOA) within a global chemistry–climate model (UKCA). Both dry and wet deposition within the UKCA model are extended to consider precursors of SOA. The oxidation mechanism describing SOA formation is also extended by adding a reaction intermediate, with SOA yields that are dependent on oxidant concentrations.

This work introduced a quantitative stratigraphic framework within a source-to-sink numerical code, pyBadlands, and evaluated two stratigraphic interpretation techniques. This quantitative framework allowed us to quickly construct the strata formations and automatically produce strata interpretations. We further showed that the accommodation succession method, compared with the trajectory analysis method, provided more reliable interpretations as it is independent of time-dependent processes.

A new numerical model for clouds is presented. It is designed for detailed studies of the small-scale behavior of cloud droplets within a domain large enough to model cloud field. To achieve this, droplets are modeled in a Lagrangian manner and calculations are done on GPU accelerators. Comparison with models that use Eulerian descriptions of droplets reveals discrepancies in the amount of precipitation. This suggests that some effects important for rain production are missing in current models.

The numerical implementation of an immersed boundary method in the atmospheric solver Meso-NH is presented. This technique models fluid–solid interaction and allows for the simulation of urban flows by considering buildings to be part of the resolved scales. This study constitutes a first robust step towards a better understanding of the interactions between weather and cities and better predictions of such interactions.