Supplementary report to the final report of the coral reef expert group: S4. Model to inform the design of a Reef Integrated Monitoring and Reporting Program

[Extract] This project developed a model to inform coral reef monitoring and management under the Reef 2050 Integrated Monitoring and Reporting Program (RIMReP) and the Reef 2050 Long-Term Sustainability Plan (Reef 2050 Plan). The model combines spatial statistical analyses with a mechanistic understanding of coral community dynamics. The purpose of the model is to analyse coral status and trend, and to guide the design of a coral monitoring program that most effectively captures these dynamics in space and time. This model uses per cent cover of hard corals and benthic composition as key indicators of reef state. Input variables include environmental data (e.g. temperature, salinity, sediment covers) and disturbance history (e.g. tropical cyclones, bleaching, water quality and outbreaks of the crown-of-thorns starfish). The model is calibrated against 20 years of in situ coral monitoring data and remotely sensed observations (1996-2015). A dual classification of all Great Barrier Reef (Reef) reefs was established based on (i) their benthic community composition and (ii) their coral cover trajectory over the 1996-2015 period, as a potential tool to stratify the future reef monitoring design. Both classifications, along with model outputs of coral cover, are available as a set of spatial layers (0.01 degree resolution).An accessible copy of this report is not yet available from this repository, please contact [email protected] for more information

A robust operational model for predicting where tropical cyclone waves damage coral reefs

International audienceTropical cyclone (TC) waves can severely damage coral reefs. Models that predict where to find such damage (the 'damage zone') enable reef managers to: 1) target management responses after major TCs in near-real time to promote recovery at severely damaged sites; and 2) identify spatial patterns in historic TC exposure to explain habitat condition trajectories. For damage models to meet these needs, they must be valid for TCs of varying intensity, circulation size and duration. Here, we map damage zones for 46 TCs that crossed Australia's Great Barrier Reef from 1985–2015 using three models – including one we develop which extends the capability of the others. We ground truth model performance with field data of wave damage from seven TCs of varying characteristics. The model we develop (4MW) out-performed the other models at capturing all incidences of known damage. The next best performing model (AHF) both under-predicted and over-predicted damage for TCs of various types. 4MW and AHF produce strikingly different spatial and temporal patterns of damage potential when used to reconstruct past TCs from 1985–2015. The 4MW model greatly enhances both of the main capabilities TC damage models provide to managers, and is useful wherever TCs and coral reefs co-occur

GREMO: A GIS-based generic model for estimating relative wave exposure

Abstract: Wave exposure plays a major role in shaping the ecological structure of nearshore communities, with different community types able to survive and/or thrive when typically exposed to different levels of wave energy. This can be quantified by taking direct field measurements with wave buoys over time and then manipulating the data to derive typical conditions. However, taking these measurements is only feasible for very limited areas due to logistical constraints, and generating them with numerical wave models can also be expensive to run and may require data inputs that are either lacking or are highly uncertain. Instead, the relative differences in wave exposure between places (relative wave exposure) may be sufficient to distinguish between different community types. It is possible to approximate relative wave exposure using a cartographic approach. Typically this involves measuring the relative shelter or openness of a particular location based on the distances from it to the nearest potential wave blocking obstacle in all directions with provides an approximation of fetch. Given that dominant wind speed and direction data is available for a particular site, these fetch distances can be manipulated to estimate the potential wave climate at that site, with some models going as far as to link this to linear wave theory in order to calculate wave power. This works because the extent to which large waves can form, and to which seas are 'fully developed', is constrained by wind velocity, time and fetch. Mapping relative wave exposure in this relatively simple way could be used to predict the spatial distribution of broad categories of ecological community types, especially where this information is difficult to collect using more direct methods. Despite its relative efficiency and simplicity, running a cartographic-based relative exposure model for more than a local study area quickly becomes computationally intensive, which drives the need to set up the model to run as quickly as possible while minimizing the risk of not detecting potential wave blocking obstacles, and thus underestimating the wave exposure. Yet surprisingly, no studies have tested the sensitivity of the relative wave exposure estimates that these models produce to variation in how key factors, such as the density of points from which fetch distances are measured (point spacing), the angle increment at which the fetch lines are drawn around each point (fetch angle spacing), and the adjustment of fetch line lengths based on bathymetry, are set in the model. This paper presents a preliminary analysis that shows the extent to which estimated relative wave exposure changed when the above model settings were varied for four case study areas within the Great Barrier Reef selected for their characteristic spatial arrangement (number and density) of obstacles. This was done using a new GIS-based generic model for estimating relative wave exposure (GREMO) which integrates many existing techniques into a single modeling platform

Coral Reef Exposure to Damaging Tropical Cyclone Waves in a Warming Climate

Tropical cyclones generate large waves that physically damage coral communities and are commonly cited as a worsening threat to coral reefs under climate change. However, beyond projections of ocean basin-scale changes in cyclone intensity, the other determinants of future coral reef damage such as cyclone size and duration remain uncertain. Here, we determine the extent to which downscaled cyclones represent observed cyclone characteristics that influence wave damage to Australian coral reef regions. We then investigate mid-century (2040–2060) and end of century (2080–2100) downscaled tracks to assess whether cyclone characteristics will change with future warming under a high-emissions scenario. We find that spatial uncertainties in downscaled cyclogenesis and track positions limit estimates of reef damage for individual coral reefs and regions. Further, the models are unable to reproduce the most reef damaging cyclones for any of the regions. The downscaled tracks capture observed cyclone characteristics, such as size, impacting the Great Barrier Reef well, but perform poorly for the Northern Territory, with mixed performance for the Coral Sea and Western Australia. We find no clear evidence that cyclones will cause more damage to Australian coral reef regions in the future, at least based on the climate models and downscaling approach examined here. There is increasing interest in using tropical cyclone projections to assess future coral reef exposure to damaging waves. We recommend caution when interpreting such projections due to large uncertainty in the mechanisms that influence reef damaging tropical cyclone characteristics and how these will change with future warming

Reef state and performance as indicators of cumulative impacts on coral reefs

Coral bleaching, cyclones, outbreaks of crown-of-thorns seastar, and reduced water quality (WQ) threaten the health and resilience of coral reefs. The cumulative impacts from multiple acute and chronic stressors on “reef State” (i.e., total coral cover) and “reef Performance” (i.e., the deviation from expected rate of total coral cover increase) have rarely been assessed simultaneously, despite their management relevance. We evaluated the dynamics of coral cover (total and per morphological groups) in the Central and Southern Great Barrier Reef over 25 years, and identified and compared the main environmental drivers of State and Performance at the reef level (i.e. based on total coral cover) and per coral group. Using a combination of 25 environmental metrics that consider both the frequency and magnitude of impacts and their lagged effects, we find that the stressors that correlate with State differed from those correlating with Performance. Importantly, we demonstrate that WQ metrics better predict Performance than State. Further, inter-annual dynamics in WQ (here available for a subset of the data) improved the explanatory power of WQ metrics on Performance over long-term WQ averages. The lagged effects of cumulative acute stressors, and to a lesser extent poor water quality, correlated negatively with the Performance of some but not all coral groups. Tabular Acropora and branching non-Acropora were the most affected by water quality demonstrating that group-specific approaches aid in the interpretation of monitoring data and can be crucial for the detection of the impact of chronic pressures. We highlight the complexity of coral reef dynamics and the need of evaluating Performance metrics in order to prioritise local management interventions

Risk‐sensitive planning for conserving coral reefs under rapid climate change

Coral reef ecosystems are seriously threatened by changing conditions in the ocean. Although many factors are implicated, climate change has emerged as a dominant and rapidly growing threat. Developing a long‐term strategic plan for the conservation of coral reefs is urgently needed yet is complicated by significant uncertainty associated with climate change impacts on coral reef ecosystems. We use Modern Portfolio Theory to identify coral reef locations globally that, in the absence of other impacts, are likely to have a heightened chance of surviving projected climate changes relative to other reefs. Long‐term planning that is robust to uncertainty in future conditions provides an objective and transparent framework for guiding conservation action and strategic investment. These locations constitute important opportunities for novel conservation investments to secure less vulnerable yet well‐connected coral reefs that may, in turn, help to repopulate degraded areas in the event that the climate has stabilized

Lavoro totale

Le componenti culturali, creative e relazionali investono in modo crescente gli ambiti dell’innovazione sociale e dell’auto-imprenditorialità e come tali vengono ampiamente studiate, ma è solo spostando l’attenzione dalle varietà del lavoro cognitivo alle forze che lo determinano che possiamo tentare di cogliere e interpretare la dinamica del cambiamento in atto. Apprendimento continuo, autonomia, responsabilità, flessibilità, individualizzazione, svalorizzazione e cooperazione diventano così traiettorie di sviluppo del lavoro e non contingenze di alcuni settori o fenomeni. Analizzare le strutture che fondano l’attuale condizione del lavoro cognitivo nei campi dell’innovazione sociale e dell’auto-imprenditorialità può allora aiutarci a comprendere le forze sottostanti ai processi di riorganizzazione del lavoro in atto. L’urgenza e l’originalità di questo libro di Maurizio Busacca consistono nell’analisi di queste strutture, cercando di rintracciare ed evidenziare contraddizioni e distorsioni prima di accettare acriticamente e astoricamente le retoriche più diffuse e dirompenti, e indagando la struttura di fondo del lavoro cognitivo, nella sua dinamica storica e esistenziale, attraverso il concetto di Lavorototale-Improduttivitàmalata. Il lavoro totale si profila come una delle forme di vita economica e sociale, ma anche di patologia individuale, che già contraddistingue nel presente il lavoro cognitivo e minaccia di estendersi a settori sempre più ampi nell’immediato futuro. L’improduttività malata è il suo risvolto, o il fratello gemello. Questo libro di Maurizio Busacca ne indaga i meccanismi, anche alla luce del magistero di Franco Basaglia, e mentre ne denuncia i pericoli cerca di individuare possibili alternative o vie d’uscita