Climate and Marine Pressures

Climate Impacts on Pressure Indicators

Introduction

This section considers the relationships between the marine climate system and the indicators of human pressures on the OSPAR Maritime Area due to Hazardous Substances and Eutrophication (HASEC) and Human Activities (EIHA), Offshore Industry (OIC) and Radioactive Substances (RSC). Regulation is the main factor affecting the indicators of contaminants, such that many of the indicators of human pressures have an indirect or very limited connection to the marine climate system. The climate drivers of principal interest for hazardous substances, eutrophication and similar human pressures are related to atmospheric transport and deposition, run-off, storm-flows and currents and upwelling. In the relevant assessment reports, climate change is highlighted as a complicating factor when trying to understand the impacts of eutrophication as the respective effects on biological communities and dissolved oxygen levels can be similar.

The indicator assessments note that increased water temperature could affect primary production and then indirectly nutrient concentrations through the seasonal cycle. At the catchment level, more frequent extreme events could affect nutrient inputs. For dissolved oxygen, the impacts of climate change on oceanographic processes and oxygen deficiency are considered a key knowledge gap. Indicators with biological components listed under ’Human Pressures’, chlorophyll-a and Phaeocystis, might be affected by changes in marine climate with potential impacts on wider marine ecosystems.

The effect of changing weather patterns and currents on the distribution of marine litter is highlighted. For dredged material, impacts of erosion, and patterns of transportation and deposition of sediments is noted, as is the important role that this material can play in the mitigation of sea level rise through coastal protection.

The links to climate noted within the assessments are repeated in Tables 1 and 2 to give an initial overview of likely issues. This initial analysis will also help indicate where future assessments could start to address the links between climate change and ocean acidification and the indicator in question.

Beyond the specifications of the assessments of the impacts of human activities produced for the IA 2017, the wider literature identifies important links between climate change and pressures that are key areas of developing understanding. The implications of climate change and ocean acidification could act on the sources of the pressure as well as on the effects. For example, AMAP (2017) noted that the decline in sea ice thickness and extent, along with changes in the timing of ice melt, can affect other pressures through enabling a wider range of human activities to take place (including oil and gas exploitation, mining, tourism, shipping, fisheries, and other economic development). AMAP noted in particular the need for adaptation activity to consider the potential interaction between all the pressures, and include the links to climate change. While the links between the impacts of a changing marine climate and marine pressures or activities are particularly evident in the Arctic, many similar interactions are likely to occur across the OSPAR Maritime Area as a whole.

Climate Impacts on Indicators for Hazardous Substances and Eutrophication

Table 1 highlights how and where marine climate has been identified within the IA 2017 common indicator assessments of human pressures linked to hazardous substances and eutrophication on the OSPAR Maritime Area. The third column identifies some of the potential implications of climate change and ocean acidification associated with these indicator assessments.

Climate Impacts on Human Activities, Offshore Industry and Radioactive Substances

Table 2 highlights how and where marine climate has been identified within the IA 2017 common indicator assessments or most recent periodic evaluations of human activities, offshore industry and radioactive Substances in the OSPAR Maritime Area. The third column identifies some of the potential implications of climate change and ocean acidification associated with these indicator assessments