Depletion of stratospheric ozone allows larger doses of harmful solar ultraviolet (UV) radiation to reach the surface leading to increases in skin cancer and cataracts in humans and other impacts, such as crop damage. Ozone also affects the Earth's radiation balance and, in particular, ozone depletion in the lower stratosphere (LS) exerts an important climate forcing. While most long-lived ozone-depleting substances (ODSs, e.g. chlorofluorocarbons, CFCs) are now controlled by the United Nations Montreal Protocol and their abundances are slowly declining, there remains significant uncertainty surrounding the rate of ozone layer recovery. Although signs of recovery have been detected in the upper stratosphere and the Antarctic, this is not the case for the lower stratosphere at middle and low latitudes. In fact, contrary to expectations, ozone in this extrapolar lower stratosphere has continued to decrease (by up to 5% since 1998). The reason(s) for this are not known, but suggested causes include changes in atmospheric dynamics or the increasing abundance of short-lived reactive iodine and chlorine species. We will investigate the causes of this ongoing depletion using comprehensive modelling studies and new targeted observations of the short-lived chlorine substances in the lower stratosphere. While the Montreal Protocol has controlled the production of long-lived ODSs, this is not the case for halogenated very short-lived substances (VSLS, lifetimes <6 months), based on the belief that they would not be abundant or persistent enough to have an impact. Recent observations suggest otherwise, with notable increases in the atmospheric abundance of several gases (CH2Cl2, CHCl3), due largely to growth in emissions from Asia. A major US aircraft campaign based in Japan in summer 2021 will provide important new information on how these emissions of short-lived species reach the stratosphere via the Asian Summer Monsoon (ASM). UEA will supplement the ACCLIP campaign by making targeted surface observations in Taiwan and Malaysia which will help to constrain chlorine emissions. The observations will be combined with detailed and comprehensive 3-D modelling studies at Leeds and Lancaster, who have world-leading expertise and tools for the study of atmospheric chlorine and iodine. The modelling will use an off-line chemical transport model (CTM), ideal for interpreting observations, and a coupled chemistry-climate model (CCM) which is needed to study chemical-dynamical feedbacks and for future projections. Novel observations on how gases are affected by gravitational separation will be used to test the modelled descriptions of variations in atmospheric circulation. The CTM will also be used in an 'inverse' mode to trace back the observations of anthropogenic VSLS to their geographical source regions. The models will be used to quantify the flux of short-lived chlorine and iodine species to the stratosphere and to determine their impact on lower stratospheric ozone trends. The impact of dynamical variability will be quantified using the CTM and the drivers of this determined using the CCM. The model results will be analysed using the same statistical models used to derive the decreasing trend in ozone from observations, including the Dynamical Linear Model (DLM). Overall, the results of the model experiments will be synthesised into an understanding of the ongoing decrease in lower stratospheric ozone. This information will then be used to make improved future projections of how ozone will evolve, which will feed through to the policy-making process (Montreal Protocol) with the collaboration of expert partners. The results of the project will provide important information for future international assessments e.g. WMO/UNEP and IPCC reports.

For the majority of cancers, early detection results in better survival. Oral cancer is one of the few cancers that is visible and many of these cancers are preceded by a potentially malignant lesion where medical intervention can prevent the development of cancer. Taken together, oral cancer presents an opportunity for early detection. However, identifying which oral lesion has a propensity to become oral cancer is not straightforward without specialised training and this problem is confounded by the lack of specialists who are trained in this expertise particularly in low- and middle-income countries, where the majority of oral cancers are diagnosed. One innovative approach to overcome this is to develop an artificial intelligence algorithm to classify oral lesions into those that are benign and those that are potentially malignant or are occult cancer so that patients can be triaged accordingly to receive appropriate clinical management. In this project, we propose to work within a multi-disciplinary, international team to collate a library of images from existing and prospective collections that will facilitate the development of an artificial intelligence algorithm that will be tested and validated. The outcome of this project will pave the way for further rigorous testing, development of an App incorporating this automated tool and clinical validation for the early detection of oral cancer. The development of an automated tool for the classification of oral lesions will facilitate the identification of patients most at risk to develop oral cancer so that these individuals can be managed appropriately. This project is particularly impactful in the low- and middle-income countries as the majority of the global burden of oral cancer is found in these countries.

Depletion of stratospheric ozone allows larger doses of harmful solar UV radiation to reach the surface leading to increases in skin cancer and cataracts in humans and other impacts, such as crop damage. Ozone also affects the Earth's radiation balance and, in particular, ozone depletion in the lower stratosphere (LS) exerts an important climate forcing. While most long-lived ozone-depleting substances (e.g. CFCs) are now controlled by the United Nations Montreal Protocol and their abundances are slowly declining, there remains significant uncertainty surrounding the rate of ozone layer recovery. Changes in the LS may cause delayed ozone recovery or even additional depletion, and can also have important effects on climate. One key uncertainty, highlighted in the WMO/UNEP 2014 Assessment of Stratospheric Ozone Depletion, is the increasing importance of uncontrolled chlorine-containing very short-lived substances (VSLS) which can reach the LS and cause ozone depletion. While significant amounts of brominated VSLS are known to be emitted naturally from the oceans, recent publications also show a rapid, unexpected and unexplained increase in anthropogenic chlorinated VSLS (Cl-VSLS), especially in E and SE Asia. Some of these Cl-VSLS will reach the stratosphere via deep convection in the tropics (through the tropical tropopause layer) or via the Asian Summer Monsoon (ASM) or the E Asian Winter Monsoon. The Montreal Protocol is arguably the world's most successful environmental agreement. By controlling the production and emission of long-lived ODSs, it has set the ozone layer on the road to recovery. However, short-lived halogenated compounds (lifetimes <6 months) have so far not been included, based on the belief that they would not be abundant or persistent enough to have an impact. Recent observations suggest otherwise; calculations in this proposal suggest that Cl-VSLS may delay the recovery of the Antarctic Ozone Hole (to 1980 levels) by up to 30 years. Fortunately, the Montreal Protocol has a regular review process which allows amendments to deal with new threats to the ozone layer and climate, e.g. the recent 2016 success of including limits to the production of hydrofluorocarbons (HFCs). This proposal takes advantage of UEA's heritage in atmospheric halocarbon measurements to obtain novel observations of chlorine compounds in the key E/SE Asia region and in the global mid-upper troposphere. Surface observations will be targeted in the key winter periods when we know that we will be able to detect polluted emissions from China, a likely major emitter of Cl-VSLS globally. We will extend the suite of gases currently measured by the CARIBIC in-service global passenger aircraft to include several newly-identified VSLS. This will allow us to investigate the distribution of these VSLS over a much wider geographical area, to identify source regions and to assess longer term changes in their atmospheric abundance. Our observations will be combined with detailed 3-D modelling at Leeds and Lancaster, who have world-leading expertise and tools for the study of atmospheric chlorine. One model will be used in an 'inverse' mode to trace back the observations of anthropogenic VSLS to their source regions. Overall, the models will be used to quantify the flux of halogenated ozone-depleting gases to the stratosphere and to determine their ozone and climate impact. We will calculate metrics for ozone depletion and climate change and feed these through to the policy-making process (Montreal Protocol) with the collaboration of expert partners. The results of SISLAC will provide important information for future international assessments e.g. WMO/UNEP and IPCC reports.

Long-term measurements of the atmospheric composition are required for a full understanding of the effects of human emissions of greenhouse gases and pollutants. For historic reasons, the network of observing stations run under the auspices of the World Meteorological Organisation's Global Atmospheric Watch program has some regions which are well studied (e.g. Europe and North America) and some which are not. One region where the observing capability is limited is that part of Southeast Asia and the West Pacific known as the 'Maritime Continent'. In this project, we will work with the University of Malaya and the Malaysian Meteorological Department to develop a high-quality, long-term atmospheric monitoring program at the new field station at Bachok on the Malaysian peninsula. This site is extremely well located for studies of the outflow of the rapidly developing Southeast Asian countries, as well as for the interaction of that air with the much cleaner atmosphere in the southern hemisphere. The Universities of Cambridge and East Anglia both have experience in making long-term measurements. In particular UEA have operated a well-instrumented observing site at Weybourne on the north Norfolk coast for well over a decade. This expertise will be used to develop the existing capability in Malaysia and to design and implement a programme of long-term measurements at Bachok. The focus of the measurements in the first instance will be greenhouse gases, ozone depleting substances, and chemical pollutants. In addition we will be encouraging the involvement of other interested scientists in NCAS Composition, the UK more generally and beyond to strengthen the planned measurement program. A demonstration activity will be arranged in the winter monsoon season when the flow is strongly from Southeast Asia. This activity will have two aims: (i) ensuring high quality measurements are made at the site; and (ii) determine the characteristics of the site and its suitability for the assessment of both global and regional atmospheric composition. Many of the measurements made in this activity will then be continued in to the monitoring programme. It is important to ensure that such measurements are fully exploited, and to this end we will both collaborate with partners in Taiwan and Australia and develop a modelling strategy for the interpretation of the data in conjunction with UK modelling groups including those at Cambridge, UEA and within NCAS. Exchange visits will be used for training purposes and for the development of collaborative interpretive studies (and peer-reviewed publications). Finally, a major scientific conference will be held towards the end of the project, linking in to international programs such as WMO-GAW, IGAC or SOLAS.

This proposal is to develop and deploy for the first time lightweight low cost (disposable) multi-species chemical sondes to address limitations in composition measurement capability in the troposphere and low stratosphere. The sondes would incorporate state of the art CO, O3 and CO2 sensors developed by the applicants, and would be launched on standard meteorological balloons flown by National Weather Services (thus providing T, P, RH). The intention is that the sonde be suitable for use in global sonde networks such as SHADOZ and GRUAN as well as for stand-alone use, with applicability to both short term case studies (e.g. transport, chemical processes) and long term monitoring (for example linked to trend detection and climate change). The project will be in four phases: - Development and construction: involving integration of chemical sensors into a sensor module and its interface with the existing Vaisala RS92 and the new RS41 radiosonde systems. - Testing and validation: to be carried out in the JOSIE atmospheric simulation chamber, on simultaneous flights with conventional ozone sondes and in parallel with flights by the NERC FAAM research aircraft. - Field deployment: to be conducted as a) an intensive field activity as part of a larger measurement campaign, and b) regular measurement for 12-18 months. These deployments will be in Malaysia and will be used in studies of the tropical atmosphere. - Data analysis: statistical analysis of composition profiles and comparisons with the NAME and UKCA models to study chemical and transport processes in the tropical tropopause layer (TTL) and the transport of constituents in the free troposphere over Southeast Asia. We have, together with our project partners, the expertise and knowledge to develop and prove these new composition sondes which have the potential to revolutionise atmospheric measurement programmes through their ability to be launched routinely by operational meteorological agencies with minimum infrastructure.