In the real world the atmosphere, oceans and land surface are closely interconnected, and yet prediction systems tend to treat them in isolation. Those feedbacks are often illustrated in natural hazards, such as when strong winds lead to large waves and coastal damage, or when prolonged rainfall leads to saturated ground and high flowing rivers. For the first time, we have attempted to represent some of the feedbacks between sky, sea and land within a high-resolution forecast system for the UK.

Igneous intrusions in sedimentary basins have a profound effect on the thermal structure of the hosting sedimentary rocks. In this paper, we present a user-friendly 1-D FEM-based tool, SILLi, that calculates the thermal effects of sill intrusions on the enclosing sedimentary stratigraphy. The motivation is to make a standardized numerical toolkit openly available that can be widely used by scientists with different backgrounds to test the effects of magmatic bodies in a wide variety of settings.

The land model integrated into the Energy Exascale Earth System Model was extended to include snow redistribution (SR) and lateral subsurface hydrologic and thermal processes. Simulation results at a polygonal tundra site near Barrow, Alaska, showed that inclusion of SR resulted in a better agreement with observations. Excluding lateral subsurface processes had a small impact on mean states but caused a large overestimation of spatial variability in soil moisture and temperature.

This paper introduces a new version of diagnostic software (COSP2) intended to facilitate more straightforward comparisons between climate models and observational cloud datasets. This version allows users to more closely incorporate their own models assumptions within COSP, while also being computationally more efficient and straightforward for users to extend and build upon.

This paper introduces a novel approach to simulating ice-free clouds. The key process is formation and transport of cloud droplets that are represented through Lagrangian particles referred to as super-droplets. Each super-droplet represents a multitude of natural cloud droplets. The essential component of the scheme that makes it different and more efficient from previous approaches is the presence of super-droplets only within a cloud.

Improved projections of future Arctic and boreal ecosystem transformation require improved land surface models that integrate processes specific to these cold biomes. To this end, this study lays out relevant new parameterizations in the ORCHIDEE-MICT land surface model. These describe the interactions between soil carbon, soil temperature and hydrology, and their resulting feedbacks on water and CO₂ fluxes, in addition to a recently developed fire module.

This paper includes the development of a new aerosol module in the air quality model CHIMERE to improve particulate matter (PM) simulation. The results of the model are compared to numerous measurements over Europe to evaluate the strengths and weaknesses of the model.

Previous studies indicate that fluxes of heat, water, and carbon between the land surface and atmosphere are substantially more predictable than the performance of the current crop of land surface models would indicate. This study uses simple empirical models to estimate the amount of useful information in meteorological forcings that is available for predicting land surface fluxes. These models can be used as benchmarks for land surface models and may help identify areas ripe for improvement.

Shingle is a new approach to describing and generating spatial mesh discretisations for multi-scale geophysical domains. Its novel use of an extendable, hierarchical formal grammar and natural language basis for geophysical features achieves robust reproduction and enables consistent comparison between models. This is designed to support the increase in complexity as models include a greater range of spatial scales and future-proof simulation set-up.

This paper compares results of developmental versions of a widely used climate model. The simulations only differ in the choice of how to model the sub-grid-scale physics in the atmospheric model. This work is novel because it is the first time that a particular physics option has been tested in a fully coupled climate model. Here, we demonstrate that this physics option has the ability to produce credible coupled climate simulations, with improved metrics in certain fields.

This paper describes the ALADIN System that has been developed by the international ALADIN consortium of 16 European and northern African partners since its creation in 1990. The paper also describes how its model configurations are used by the consortium partners for their operational weather forecasting applications and for weather and climate research.

We explored an inverse modeling technique to interpret global atmospheric measurements of CO₂ and the ratio of its stable carbon isotopes (δ¹³C). We detected the possible underestimation of drought stress in biosphere models after applying combined atmospheric CO₂ and δ¹³C constraints. This study highlights the importance of improving the representation of the biosphere in carbon–climate models, in particular in a world where droughts become more extreme and more frequent.

Global simulations of atmospheric chemistry are generally conducted with off-line chemical transport models (CTMs) driven by archived meteorological data from general circulation models (GCMs). The off-line approach has the advantages of simplicity and expediency, but it is unable to reproduce the GCM transport exactly. We investigate the cascade of errors associated with the off-line approach using the GEOS-5 GCM and GEOS-Chem CTM and discuss improvements in the use of archived meteorology.

This paper presents a new interactive scheme for ocean surface albedo suited for the current generation of Earth system models. This scheme computes the ocean surface albedo accounting for the spectral dependence (across a range of wavelengths between 200 and 4000 nm), the characteristics of incident solar radiation (direct of diffuse), the effects of surface winds, chlorophyll content and whitecaps in addition to the canonical solar zenith angle dependence.

This paper describes a fast new method for calculating how much sunlight is absorbed and reflected by forests and other types of vegetation, rigorously taking account of the complex 3-D structure. Careful evaluation shows it to perform well even in difficult scenes with snow on the ground. The method is suitable for use within the computer models used to make weather and climate forecasts, where it has the potential to improve predictions of near-surface temperature and photosynthesis rates.

We propose a decadal forecast recalibration strategy (DeFoReSt) which simultaneously adjusts unconditional and conditional bias, as well as the ensemble spread while considering the typical setting of decadal predictions, i.e., model drift and a climate trend. We apply DeFoReSt to decadal toy model data and surface temperature forecasts from the MiKlip system and find consistent improvements in forecast quality compared with a simple calibration of the lead-time-dependent systematic errors.

Historical emission trends are key inputs to Earth systems and atmospheric chemistry models. We present a new data set of historical (1750–2014) anthropogenic gases (CO, CH₄, NH₃, NO_x, SO₂, NMVOCs, BC, OC, and CO₂) developed with the Community Emissions Data System (CEDS). This improves on existing inventories as it uses consistent methods and data across emissions species, has annual resolution for a longer and more recent time series, and is designed to be transparent and reproducible.

Human alteration of land cover has caused CO₂ that is stored in forest biomass and soil to be released into the atmosphere and thus contribute to global warming. Global vegetation models that are used to quantify such carbon emissions from land use change traditionally rarely include shifting cultivation and secondary forest age dynamics. In this study, we expanded one vegetation model to include these features. We found that carbon emissions from land use change are estimated to be smaller.

One-third of the global land area is covered with grasslands which are grazed by or mowed for livestock feed. These areas contribute significantly to the carbon capture from the atmosphere when managed sensibly. To assess the effect of this management, we included different options of grazing and mowing into the global model LPJmL 3.6. We found in polar regions even low grazing pressure leads to soil carbon loss whereas in temperate regions up to 1.4 livestock units per hectare can be sustained.

Earth system models of intermediate complexity generally have a simplified model physics and a coarse model resolution. In this work we present the inclusion of an online dynamical downscaling of temperature and precipitation in such a model. This downscaling explicitly takes into account sub-grid topography. With this new model functionality we are able to simulate temperature and precipitation on a 40 km grid for the whole Northern Hemisphere from the native model resolution.

Marine phytoplankton accounts for half of global primary production. Phytoplankton size is an important trait affecting its fitness and ecosystem functioning. We have developed a plankton model with continuous size distribution for phytoplankton and applied it in the North Pacific. This model is able to capture the general patterns of phytoplankton size distribution in the real ocean and can be used for understanding the mechanisms controlling phytoplankton size structure and diversity.