Effects chain – Example presentation from the ‘trade and industry’ action | Umweltbundesamt

Climate changes relevant to the action field

State: Hot days, soil humidity

Germany is experiencing an increase in the frequency of hot and dry years. Prior to 2014 there were no years in which the annual mean temperature exceeded 10 °C. With regard to the period since 2018, the annual mean temperature – only for 2021 – was still below this value. In 2018 and 2022 the highest value so far was reached amounting to 10.5 °C in both years. In parallel with increasing mean temperatures, the frequency of hot days on which the temperature rises to 30 °C and above is also increasing. Nationwide Germany now has on average roughly 10 hot days per annum compared to 3 hot days in the middle of the 20th century (cf. figure 5). When high temperatures occur in tandem with negligible precipitation in summer as for instance in 2018, 2019 and 2022, this can entail intensive and also prolonged dry phases.

Impacts of climate change

Impact: WW-I-10: Water temperature of watercourses

As air temperature rises, the temperature of watercourses rises too, especially when water levels are low owing to drought. In all regions where fish occur – except for the grayling region. The temperature of watercourses increased significantly in past decades. Extremely high water body temperatures and associated lack of oxygen as in 2018 have massive ecological impacts. In order to protect watercourses, any water use in trade and industry for production or cooling purposes is subject to an appropriate licence. This licence stipulates at what temperature, quality and volume water can be fed back into the water bodies after utilisation. This occurred, for example, in the hot summers of 2003, 2006, 2018 and latterly 2022, when owing to prolonged heat and drought, restrictions were imposed on thermal discharge into various water bodies. Some companies, for example those active in the chemical industry, had to curtail their production thus enabling them to continue meeting the discharge conditions laid down in their licence.

Adaptations – activities and results

Response: IG-R-3: Water procurement in the processing industry

In particular regarding water-intensive industries such as the chemical, metal or paper industries, the reduction of water demand is an important measure in order to increase resilience and to reduce dependence on water resources. In order to use as little water as possible in terms of raw or processing material, and in order to use the abstracted water as efficiently as possible, companies might for instance consider – within the framework of their environmental management – embracing an in-house water management system, using water in a circulatory system, employing water-saving technologies or using other substances such as emulsions in lieu of water. Overall, water procurement in the processing industry decreased significantly since 1991, although this decrease has slowed down since 2001. As far as government support is concerned, the saving of water in trade and industry can be strengthened by incentives and minimum standards, for example by stipulating a minimum standard for efficient industrial water use as defined according to the current state of the art.