Kilimanjaro is changing. There has been extensive deforestation. The summit ice-fields are retreating. The water supply on the lower slopes of the mountain is becoming more unreliable with more flash flooding and more periods of drought. The main cause of the summit ice retreat is that the climate is becoming drier, with less precipitation (hence accumulation of snow), and fewer clouds meaning more sunlight which causes intense sublimation and hence ablation. The reasons for drying, however, are not well understood. They are believed to be a combination of free air changes due to changes in the Indian ocean upstream to the east, and local-scale land use change (such as deforestation) which may dry out the air locally. Because the mountain is in the tropics, the sun is strong and it heats the mountain each day. This causes upslope winds that help transport moisture from the rainforests on the lower slopes to the summit region where it is deposited as snow (or at the very least forms cloud that protects the ice fields from sunlight). The upper air itself is normally extremely dry, so it is possible that deforestation could in theory cause ice field decline. Unfortunately, although we have much high publicity research focusing on the ice-field decline, there is no field data on the slopes of the mountain that measures climate, although high profile and well-funded international campaigns have looked at the mountain summit in isolation. There are also lots of computer models of Kilimanjaro's climate and the effects of deforestation but they have no data against which to validate their simulations. This research proposes to fill this gap by collecting field observations of temperature and moisture on both the windward dry north-east slope and the lee forested south-west slope, expanding on data already collected by the research team since 2004. The funding will allow collection of two years of data on the south-west slope (10 years in total), and two years on the drier north-eastern slope. As well as the comparison between slopes, we will collect data from subsidiary studies at a more local scale (at given elevations on the south-west slope) examining the contrast between vegetated and deforested/unvegetated locations. We will be able to compare our results with free-air temperatures and moisture at the same elevations (from reanalysis products which are based on weather balloon records) which will show us how the mountain surface itself is influencing the climate. We will be able to compare the two slopes to quantify the large scale effect of vegetation (the south-west slope has healthy forest cover but the north-east slope does not) and local scale effects by comparing vegetated/non-vegetated readings on the south-west slope. We will be able to use the differences we obtain to reconstruct mountain climate back in the past, and also to compare/validate the computer models that are attempting to simulate the effects of land-use change on the mountain.

Phosphorus, one of the major three nutrients for plants, is required for plant growth, and it serves as an indicator for global environmental sustainability. It is important to understand the variations of phosphate in soils and soil-water systems in order to address a number of global challenges such as food production and regulating fertilizer applications for crops grown in various soil conditions and climate regimes. The goal of this research project is to use the latest graphene-based technology to develop a low-cost sensor capable of real-time monitoring of the phosphorus content in soil. This collaborative project between researchers at the U.S. institutions of Kansas State University and the University of Alabama at Huntsville, and the U.K. institution of the University of Sheffield, will be conducted by an interdisciplinary team with expertise in soil and water science, geology, electrical engineering, and the fundamental chemistry and physics of soil-graphene interactions. Development of such sensors will enable farmers to choose the right amount of fertilizer to apply to the fields. This research project aims to develop an additively-manufactured graphene sensor array and a portable wireless system for continuous in-field monitoring of electrochemical signals. Such a system would be applied to the mapping of soil phosphates in diverse agricultural landscapes in the US Midwest (Kansas) and the UK East Midlands (Derbyshire Dales and Peak District). Structurally and chemically tailored graphene materials will be used to print graphene sensors with quasi-three-dimensional and porous graphene morphologies. The materials will be designed to achieve high electrical conductivity as well as reversible and high electron charge-transfer characteristics when exposed to soil phosphates. A fundamental understanding of phosphate ion binding with various graphene morphologies will be gained using state-of-the-art ultrafast laser spectroscopy and high-end computational modeling. A Bluetooth communication module with an Arduino platform will be constructed and interfaced with the sensor arrays for sensor data acquisition. Controlled environmental testing of spatial and temporal variations of phosphate ions over other interfering ions will be carried out at specific sites in Kansas and at Europe's largest controlled environment P3-facility housed at the University of Sheffield. The fundamental sensing characteristics and drift optimization with temperature, humidity, salinity, and soil pH will be identified and optimized for reliable data collection. Soils ranging from coarse calcareous to loamy montmorillonitic and silicate-rich soils in two countries will be utilized as testbeds to measure the sensing capabilities of the printed arrays. Furthermore, the project will explore the detection of phosphates over other interfering ions in soils, such as nitrates, silicates, and heavy metals, by using chemically-functionalized graphene sensors. This research will help to strengthen the national and economic security of both the U.S. and the U.K. and will strengthen the future workforce by bridging the gaps between science, technology, agriculture, and environmental disciplines through the training of graduate students, undergraduate students, and postdoctoral scientists.

Biomass burning aerosol (BBA) exerts a considerable impact on regional radiation budgets as it significantly perturbs the surface fluxes and atmospheric heating rates and its cloud nucleating (CCN) properties perturb cloud microphysics and hence affect cloud radiative properties, precipitation and cloud lifetime. It is likely that such large influences on heating rates and CCN will affect regional weather predictions in addition to climatic changes. It is increasingly recognised that biomass burning affects the biosphere but the magnitude of the effects need to quantified. However, BBA is a complex and poorly understood aerosol species because of the mixing of the black carbon with organic and inorganic species. Furthermore, emission rates are poorly quantified and difficult to represent in models. It is now timely to address these challenges as both measurement methods and model capabilities have developed rapidly over the last few years and are now sufficiently advanced that the processes and properties of BBA can be sufficiently constrained by measurements; these can be used to challenge the new aerosol schemes used in numerical weather prediction (NWP) and climate models. Amazonia is one of the most important biomass burning regions in the world, being significantly impacted by intense biomass burning during the dry season leading to highly turbid conditions, and is therefore a key environment for quantifying these processes and determining the influence of these interactions on the weather and climate of the region. Though previous large scale studies of BBA over Amazonia and its radiative impacts have been performed, these are now over a decade old and considerable scientific progress can be made towards addressing all of the above questions given the rapid advance of models and measurements in recent years. We are therefore proposing a major consortium programme, SAMBBA, a consortium of 7 university partners and the UK Met Office, which will deliver a suite of ground, aircraft and satellite measurements of Amazonian BBA and use this data to 1) improve our knowledge of BB emissions; 2) challenge and improve the latest aerosol process models; 3) challenge and improve satellite retrievals; 4) test predictions of aerosol influences on regional climate and weather over Amazonia and the surrounding regions made using the next generation of climate and NWP models with extensive prognostic aerosol schemes; and 5) assess the impact of .biomass burning on the Amazonian biosphere. The main field experiment will take place during September 2012 and is based in Porto Velho, Brazil. At this time of year, widespread burning takes place across the region leading to highly turbid conditions. The UK large research aircraft (FAAM) will be used to sample aerosol chemical, physical and optical properties and gas phase precursor concentrations. Measurements of radiation will also be made using advanced radiometers on board the aircraft and satellite data will also be utilised. The influences of biomass burning aerosols are highly significant at local, weather, seasonal, and climate temporal scales necessitating the use of a hierarchy of models to establish and test key processes and quantify impacts. We will challenge models carrying detailed process descriptions of biomass burning aerosols with the new, comprehensive observations being made during SAMBBA to evaluate model performance and to improve parameterisations. Numerical Weather Prediction and Climate model simulations with a range of complexity and spatial resolution will be used to investigate the ways in which absorbing aerosol may influence dynamics and climate on regional and wider scales. At the heart of the approach is the use of a new range of models that can investigate such interactions using coupled descriptions of aerosols and clouds to fully investigate feedbacks at spatial scales that are sufficiently well resolved to assess such processes.

Biomass burning aerosol (BBA) exerts a considerable impact on climate by impacting regional radiation budgets as it significantly reflects and absorbs sunlight, and its cloud nucleating properties perturb cloud microphysics and hence affect cloud radiative properties, precipitation and cloud lifetime. However, BBA is a complex and poorly understood aerosol species as it consists of a complex cocktail of organic carbon and inorganic compounds mixed with black carbon and hence large uncertainties exist in both the aerosol-radiation-interactions and aerosol-cloud-interactions, uncertainties that limit the ability of our current climate models to accurately reconstruct past climate and predict future climate change. The African continent is the largest global source of BBA (around 50% of global emissions) which is transported offshore over the underlying semi-permanent cloud decks making the SE Atlantic a regional hotspot for BBA concentrations. While global climate models agree that this is a regional hotspot, their results diverge dramatically when attempting to assess aerosol-radiation-interactions and aerosol-cloud-interactions. Hence the area presents a very stringent test for climate models which need to capture not only the aerosol geographic, vertical, absorption and scattering properties, but also the cloud geographic distribution, vertical extent and cloud reflectance properties. Similarly, in order to capture the aerosol-cloud-interactions adequately, the susceptibility of the clouds in background conditions; aerosol activation processes; uncertainty about where and when BBA aerosol is entrained into the marine bundary layer and the impact of such entrainment on the microphysical and radiative properties of the cloud result in a large uncertainty. BBA overlying cloud also causes biases in satellite retrievals of cloud properties which can cause erroneous representation of stratocumulus cloud brightness; this has been shown to cause biases in other areas of the word such as biases in precipitation in Brazil via poorly understood global teleconnection processes. It is timely to address these challenges as both measurement methods and high resolution model capabilities have developed rapidly over the last few years and are now sufficiently advanced that the processes and properties of BBA can be sufficiently constrained. This measurement/high resolution model combination can be used to challenge the representation of aerosol-radiation-interaction and aerosol-cloud-interaction in coarser resolution numerical weather prediction (NWP) and climate models. Previous measurements in the region are limited to the basic measurements made during SAFARI-2000 when the advanced measurements needed for constraining the complex cloud-aerosol-radiation had not been developed and high resolution modelling was in its infancy. We are therefore proposing a major consortium programme, CLARIFY-2016, a consortium of 5 university partners and the UK Met Office, which will deliver a suite of ground and aircraft measurements to measure, understand, evaluate and improve: a) the physical, chemical, optical and radiative properties of BBAs b) the physical properties of stratocumulus clouds c) the representation of aerosol-radiation interactions in weather and climate models d) the representation of aerosol-cloud interactions across a range of model scales. The main field experiment will take place during September 2016, based in Walvis Bay, Namibia. The UK large research aircraft (FAAM) will be used to measure in-situ and remotely sensed aerosol and cloud and properties while advanced radiometers on board the aircraft will measure aerosol and cloud radiative impacts. While the proposal has been written on a stand-alone basis, we are closely collaborating and coordinating with both the NASA ORACLES programme (5 NASA centres, 8 USA universities) and NSF-funded ONFIRE programme (22 USA institutes).