[1] Observations of gas-phase iodine species were made during a field campaign in the eastern Pacific marine boundary layer (MBL). The Climate and Halogen Reactivity Tropical Experiment (CHARLEX) in the Galápagos Islands, running from September 2010 to present, is the first long-term ground-based study of trace gases in this region. Observations of gas-phase iodine species were made using long-path differential optical absorption spectroscopy (LP-DOAS), multi-axis DOAS (MAX-DOAS), and resonance and off-resonance fluorescence by lamp excitation (ROFLEX). These measurements were supported by ancillary measurements of ozone, nitrogen oxides, and meteorological variables. Selective halocarbon and ultrafine aerosol concentration measurements were also made. MAX-DOAS observations of iodine monoxide (IO) display a weak seasonal variation. The maximum differential slant column density was 3.8 Â 10 13 molecule cm À2 (detection limit~7 Â 10 12 molecule cm À2 ). The seasonal variation of reactive iodine IO x (= I + IO) is stronger, peaking at 1.6 pptv during the warm season (February-April). This suggests a dependence of the iodine sources on the annual cycle in sea surface temperature, although perturbations by changes in ocean surface iodide concentration and solar radiation are also possible. An observed negative correlation of IO x with chlorophyll-a indicates a predominance of abiotic sources. The low IO mixing ratios measured (below the LP-DOAS detection limit of 0.9 pptv) are not consistent with satellite observations if IO is confined to the MBL. The IO x loading is consistent with the observed absence of strong ozone depletion and nucleation events, indicating a small impact of iodine chemistry on these climatically relevant factors in the eastern Pacific MBL.

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The web-based tool ARClim provides an atlas of climate change-related risk assessments spanning over 50 environmental and productive sectors in Chile. This paper illustrates the implementation of ARClim on two coastal sectors, operational downtime in fishing coves and flooding in coastal settlements, aiming to provide a tool to visualize comparative estimates of risk, which may enable decision makers and stakeholders to prioritize adaptation measures. The risk is calculated as a function of the hazard, exposure, and sensitivity. Exposure and sensitivity are characterized using present day information. To assess the hazard, wave climate for a historical period (1985–2004) and a projection (2026–2045) were modeled with six general circulation models (GCMs) for an RCP8.5 scenario. Similarly, sea-level rise was computed from 21 GCMs. Results show that the flooding hazard is mostly dependent on sea-level rise, with waves playing a minor role. However, the flooding risk is highly variable along the coast, due to differences in the exposure, which strongly depends on the population of each settlement. The analysis of increased operational downtime in fishing coves also shows risk, which is dependent of the size of each site. Lastly, limitations of the analysis and opportunities for improvement are discussed.

The economic costs of port operation downtime due to ocean swells under the RCP8.5 climate change scenario at 8 ports in Chile is evaluated. First, wave statistics for the historical period (1985-2004) and projection (2026-2045) are computed using WWIII and 6 wind models with good performance in Southeastern Pacific Ocean (Hemer, 2016). The model is calibrated with data from directional wave buoys and satellite tracks between 1980 and 2015 in Chilean coasts (Bey et al., 2016). Offshore wave data is transferred using SWAN to point in the vicinity of each port. Then, the downtime is computed by comparing wave climate and 4 different threshold values of Hs for port closure (PPEE, 1999) for representative vessels at each site. Historical and projected downtimes are expressed in hours per year. The difference in downtime between both periods is attributed to climate change. The economic impact associated with the downtime for both periods is finally estimated.Recorded Presentation from the vICCE (YouTube Link): https://www.youtube.com/watch?v=O1e_OvWAI8E

Economic costs due to operational downtime and wave overtopping under the RCP 8.5 scenario are evaluated at 7 Chilean ports located on a tectonically active-coast. Wave statistics for a historical period (1985-2004), mid-century (2026-2045) and end-of-century projections (2081-2100) are computed with a Pacific-wide model, forced by wind fields from six General Circulation Models. Offshore waves are then downscaled to each port, where downtime is computed by comparing wave heights with vessel berthing criteria. The difference in downtime between the historical and projected periods is attributed to climate change. While changes in offshore wave climate will be moderate and spatially smooth in the region, some ports will reduce and others increase downtime for mid-century projections due to local effects. By the end-of-century, however, all ports will experience downtime reduction. Additionally, by mid-century, overtopping will increase in northern ports as a combination of extreme waves and sea-level rise (SLR), while in southern ports it will be slightly reduced due to milder waves. By the end-of century, overtopping will increase in the whole region, mainly driven by SLR. Overtopping rates, however, are significantly altered by coseismic uplift/subsidence which may occur during the design-life of coastal works. Adaptation measures are finally proposed.