Climate Change Thematic Assessment

Human activities and climate change

A great number of land-based and sea-based human activities emit greenhouse gases, causing climate change and ocean acidification. The following table provides an overview of the key human activities and their trends, as assessed by the OSPAR Quality Status Report 2023.

Activities emitting greenhouse gases

A great number of land-based and sea-based human activities emit greenhouse gases, causing climate change and ocean acidification. Globally, greenhouse gas emissions continued to rise between 2010 and 2018 (Lamb et al., 2021). Atmospheric greenhouse gas emissions are not covered by OSPAR measures or reported by harmonised OSPAR methodologies, but are dealt with by the UNFCCC, the International Maritime Organization (IMO), the International Civil Aviation Organization (ICAO), the EU -where applicable- and national legislation.

Over the period 2009-2019, the Extraction of oil and gas sector (see:  Offshore Industry Thematic Assessment ) identified a decreasing trend in emissions. The offshore oil and gas industry continues to make improvements to the methodologies for quantifying these emissions, as well as develop initiatives to reduce its contribution to climate change (e.g. the World Bank’s ‘Zero Routine Flaring by 2030’ initiative).

Fuel combustion by maritime vessels is a major source of greenhouse gas emissions (see:   Human Activities Thematic Assessment ). Maritime vessels include those used in Transport – shipping, Fish and shellfish harvesting, Extraction of minerals and Tourism and leisure. Inputs include discharges from exhaust gas cleaning systems, discharges of contaminated water, and pollution from the oil or other noxious substances that can arise from accidents and operational activities such as the washing of cargo tanks or the use of antifouling paints.

Similarly, the combustion of fossil fuels in the Transport – air, Transport – land, Agriculture, Aquaculture, Urban and industrial uses (including the generation of electricity and heating) and Tourism and leisure activities and infrastructure sectors also emits greenhouse gases (see:  Human Activity Thematic Assessment ).

Changes in methods of energy generation

see:  Human Activity Thematic Assessment

As Contracting Parties transition to low-carbon energy generation and use, there will be significant changes to the main sources of energy generation. Offshore wind installations (and other technologies, such as wave, tidal stream and tidal range) in the OSPAR Maritime Area are expected to increase greatly in the next decade and beyond, primarily in the Greater North Sea and Celtic Seas Regions. The amount of offshore wind energy capacity has increased substantially since QSR 2010; turbine size, wind farm size and average distance to shore have also increased. Offshore wind energy capacity is anticipated to expand at an accelerated pace in the coming decade, and further expansion beyond 2030 is also planned. While most of this will involve fixed turbines, floating installations are now past the proof-of-concept stage and may become more prevalent. Some increase in wave and tidal energy installations, including pilot projects, is anticipated up to 2030, but significant cost reductions would be needed for these to play a significant role in energy generation. Nuclear technologies are also considered by some Contracting Parties to have a role to play in the energy transition (see:  Radioactive Substances Thematic Assessment ).

Activities to limit exposure to climate risk

Despite the focus on avoiding and reducing greenhouse gas emissions so as to mitigate climate change, some of future impacts of global warming will occur as the inevitable result of past and current emissions (also known as committed warming), and further impacts will emerge as long as greenhouse gas concentrations in the atmosphere increase. Activities in the marine and coastal environment may support adaptation to climate change impacts and reduce the exposure to climate risks such as sea level rise, coastal flooding and erosion. To address the exposure to climate risks of coastal and marine infrastructure, activities related to Coastal defence and flood protection are anticipated to increase.

Non-marine activities and their influence on the marine environment.

Forests play an integral part in the carbon cycle and help to stabilise the climate (IUCN). Each year, deforestation and forest degradation account for 5 to10 billion tonnes of CO₂-equivalent emissions. CO₂-equivalent, or CO₂e, is a measure used to standardise the climate effect of various greenhouse gases; it adjusts for the fact that each greenhouse gas has a different warming potential and atmospheric lifetime. This metric expresses emissions to an equivalent of the most common greenhouse gas (CO₂). Forestry management is thus an important factor in addressing the effects of climate change. In addition to contributing to climate change, agriculture can itself be affected by climate change (temperature change, rainfall, spread of pests and diseases). Changes to agriculture due to shifts in societal demands for plant- and animal-based products are increasingly becoming apparent. Any changes in activities in freshwater and terrestrial environments may have an influence on conditions in the coastal and marine environments.

Marine-based activities providing climate solutions

There is increasing recognition of “working with nature” to address climate risks and increase the uptake and storage of greenhouse gases in natural stores. Nature-based solutions such as the conservation and restoration of biogenic reefs, salt marshes and sea- grass beds may provide solutions to coastal flooding and coastline erosion by acting as floodplains or reducing wave exposure. Other benefits of nature-based solutions may be their ability to take up and store carbon (climate change mitigation) and their biodiversity functions. This will be revisited in the Response section.