UK natural capital accounts: 2021

• In 2019, the stock of the aspects of UK natural capital we can currently value was estimated to be worth £1.2 trillion.

• The number of outdoor recreation and tourism visits in the UK increased by 46% between 2011 and 2019.

• Renewable power generation is 21 times larger in 2020 than it was in 2003.

• UK land-use emits more greenhouse gases than it removes.

• The number of days in cities classed as "hot" has risen year-on-year, leading to the economic value of urban cooling doubling in the last four years.

Natural wealth is reflected in things like the productivity of soils and access to clean water. Any natural resource or process that supports human life, society and the economy forms an important part of our natural capital. We are estimating both the current value and what it could provide for future generations. Natural capital is an important part of a wider move to better understand "inclusive wealth".

This year we have added data on nature tourism to estimates of recreation benefits. This has improved estimation of the asset value of our stocks taking them from a little under £1 trillion to £1.2 trillion.

There are two important caveats to our work.

Natural capital estimates do not cover all services. We continue to work to encompass as much of the economic value of the natural world as possible, which is challenging given its scale and complexity.

Our asset values are not an absolute "value" of the price we would accept to sell the entire natural world. The natural world supports all life on earth, and its collapse would precipitate our own, implying infinite value.

Provisioning services are products from nature such as food, water, energy, and materials. These provisioning services include:

• agricultural biomass: the value of crops, fodder and grazing (farmed animals are not included as they are considered produced rather than natural assets, however the food they eat, such as grass and feed, is included)

• water abstraction: water removal for public water supply only

• fossil fuels extraction: production of crude oil, gas and coal

• renewable energy generation: electricity generated from renewable sources, wind, hydroelectric, solar, wave and tidal

• timber removals: wood production (also referred to as removals) is the harvesting of roundwood (trunk and branch wood) from coniferous (softwood) and broadleaved (hardwood) trees

• mineral extraction: mineral extraction largely consisting of construction mineral aggregates

• fish capture: the value of marine fish taken from mainland UK waters (aquaculture of farmed fish are excluded as farmed fish are viewed as a produced asset and not a natural asset)

Fossil fuels has seen the largest reduction, with coal declining by 93% since 2003. Renewable energy generation is approximately 21 times larger in 2020 than it was in 2003.

There was a 15% reduction in the annual value of provisioning services between 2018 and 2019, driven by fossil fuels, which fell by 37%. This can be partly attributed to decreases in oil and gas prices by 7% and 45% respectively.

Fossil fuels still account for 41% of the total provisioning services valuation.

Regulating services help to maintain the quality of the environment we rely upon. These include reducing noise, providing cooling on hot days, cleaning the air and sequestering carbon.

These regulating services include:

• carbon sequestration: the removal of climate change gases from the atmosphere is provided by a range of habitats, with woodland habitats being the primary supplier. The capacity for vegetation to remove carbon or pollutants from the air depends upon its amount and type.

• air pollutant removal: the removal of air pollutants by vegetation, which is measured in terms of the avoided healthcare costs associated with exposing the public to the pollutants removed

• urban cooling: green (parks) and blue spaces (rivers, lakes, canals) can cool urban environments on hot days, which benefits the economy by limiting loss of labour productivity and reducing use of air conditioning

• noise mitigation: vegetation acts as a buffer against noise pollution, in particular road traffic noise

Valuation methods of these regulating services differs:

• carbon sequestration uses a removal cost, using the estimated cost of carbon removal by other means and BEIS recently increased its carbon prices

• air pollutant removal uses the cost of treating ill health in humans caused by the pollutant if it were not removed 

Over the last decade, each tonne of air pollution removed was valued at £1,200 - more than five times the £220 value of a tonne of carbon sequestered. This is because pollutants, predominately PM2.5, have significant immediate effects on health, with even small removals providing large benefits to society.

Changes in how the UK models carbon sequestration by nature, primarily how peatlands are accounted for, indicate that the UK emits more greenhouse gases than it removes from land use, land use change and forestry (LULUCF). Following current guidance, the UK Natural Capital Accounts present 'gross' removals.

Cultural services are non-material benefits people obtain from natural capital, such as tourism, recreation, and aesthetic experience. Changes have been made to the way we estimate the recreational benefit of nature. These are discussed within the UK natural capital accounts: Tourism and recreation methods changes. These cultural services include:

• tourism and recreation: the spend incurred to travel to the natural environment and some expenditure incurred during the visit (parking fees, transport costs, vehicle running costs and admissions)

• house prices (recreation and aesthetic): recreation house prices include the additional expenditure on houses that are near to green (land) and blue (water) spaces, enabling people to make "free trips" to the natural environment, while aesthetic house prices include how much value is added to a house that has a view of a green and/or blue space

Since 2011, tourism and recreation has contributed an average of 83% of the annual value of cultural services.

The number of recreation and tourism visits to the outdoors has been increasing over time. Visits have increased by 1.6 billion between 2011 and 2019, with 90% of this rise seen within urban areas. The number of visits to the outdoors was also more than 5 billion for the first time in 2018.

Asset values of natural resources refer to the long-term potential (stock) of that resource to provide goods and services to humans. This contrasts with annual valuations (flows).

Asset

A natural asset is a resource that can generate goods or services to humans into the future. Asset valuation estimates the stream of services that are expected to be produced by the natural resource over a reasonably predictable time horizon see method for details.

Ecosystem services

Ecosystem services are the living (biotic) components of the Earth that provide services to humans, such as woodland.

Physical flow

The physical flow of a natural asset is the measure of its output in units appropriate to the good or service. This differs from the annual value and asset value, which measure the monetary value of a natural resource.

We have used a wide variety of sources for estimates of UK natural capital.

The Office for National Statistics (ONS) and the Department for Environment, Food and Rural Affairs (Defra) have published a summary of the principles underlying the accounts.

These accounts been compiled in line with the guidelines recommended by the United Nations (UN) System of Environmental-Economic Accounting Central Framework and System of Environmental-Economic Accounting Experimental Ecosystem Accounting principles, which are in turn part of the wider framework of the system of national accounts. UN guidance is currently under development.

We welcome feedback on any of the approaches and this output by email to natural.capital.team@ons.gov.uk.

More detailed quality and methodology information on strengths, limitations, appropriate uses, and how the data were created is available in the accompanying UK natural capital accounts methodology guide: 2021.

These experimental accounts are being continually revised to produce the best statistics with the available data and methods. We have identified any limitations of the data as well as ideas for future development. More detailed quality and methodology information on strengths, limitations, appropriate uses, and how the data were created is available in the accompanying UK natural capital accounts methodology guide: 2021.