While the global budget includes the emissions of the entire world population, the Wiesbaden clock takes regional emissions data into account. As per capita emissions in Germany - and therefore also in Wiesbaden - are above the global average, the clock runs faster here. On average, 10.3 tons of CO2 are emitted per person in Germany every year. This puts a German's emissions around 60 percent above the global average. This makes it clear that wealthier and more industrialized regions must reduce their emissions particularly quickly and consistently in order to achieve the common climate goal.

When the climate clock for Wiesbaden expires, the local CO₂ budget for Wiesbaden will be used up. This means that the local climate protection target will not be met. Every measure that reduces CO₂ emissions stabilizes the budget. Industry and commerce, transport and each of us as citizens can make a contribution here. The likelihood of exceeding the budget must give us additional incentive to step up our climate protection activities.

Since the Paris Climate Agreement, the 1.5°C target has been regarded as the key marker. The majority of climate experts assume that climate change is still manageable.

According to calculations by the German Advisory Council on the Environment (SRU), Germany has already exhausted its remaining budget for 1.5°C by 2024. The budget therefore refers to a warming of 1.75 °C - the closest mark that still corresponds to the Paris target of "well below two degrees Celsius".

Every tenth of a degree counts in climate protection: as temperatures rise, weather extremes increase and the risk of crossing tipping points grows - melting polar ice caps, the weakening of the Gulf Stream or the death of the Amazon rainforest would be the result. All of this should be an incentive to drive climate protection forward with determination.

Humans influence the climate, particularly through the release of greenhouse gases Even a warming of less than 2 °C has serious consequences worldwide. Droughts, heatwaves, heavy rainfall and other extreme weather events are on the increase and biodiversity is under threat. It is therefore important to significantly reduce greenhouse gases globally, nationally and locally. Otherwise, climate change will jeopardize safety, health and prosperity.

A CO₂ budget shows how much greenhouse gas we can still emit in order to meet the 1.75 degree target. The idea was developed in 2009 by the German Advisory Council on Global Change (WBGU) and has been updated by the German Advisory Council on the Environment (SRU) ever since - most recently in 2024 with a CO₂ budget calculator.

Such budgets help to understand how big the climate protection task is, what savings are necessary and how progress can be measured.

The Environmental Agency has calculated a local residual budget for Wiesbaden. If the city reduces its emissions by around 182,000 tons of CO₂ each year (around 8% of current emissions), the budget would be used up by around 2035.

The calculations for the Wiesbaden climate clock are based on the approach of the German Advisory Council on the Environment (SRU), its data basis and the municipal greenhouse gas balance for Wiesbaden.

The SRU publications from 2024 were used for the Wiesbaden residual budget. This incorporates emissions data (2022/23) and current scientific findings on the remaining global CO₂ budget and the warming that has already occurred.

Specifically, the Wiesbaden budget was derived from the national budget based on the share of urban emissions in total German emissions in 2022 - the last year with a complete municipal balance sheet. In contrast to the SRU, the number of inhabitants was not used as a benchmark. This is because large cities such as Wiesbaden usually have higher per capita emissions than rural municipalities due to their supra-regional functions, such as industry, universities, transport hubs or consumer and leisure facilities. A pure population allocation would therefore have led to a lower residual budget.