We use three criteria to define short-haul flights:

• the flight distance in kilometers (limit: 1,000km), or
• the travel time by other means of transportation, in particular by train (limit: 8 hours), or
• the destination is within Germany.

For the evaluation of emissions from business trips, we use the criterion of flight distance. The reason for this is that a retrospective comparison with other means of transport is no longer possible. In our evaluation, all flights with a flight distance of up to 1,000 km are therefore classified as short-haul flights.

For you as a traveler, the criterion of travel time with other means of transport is relevant for compliance with the short-haul regulation from the travel policy. In comparison to the pure kilometer limit, this is about the actual accessibility of a specific destination. When organizing your business trip, it is therefore important that you are not allowed to fly to destinations if you can reach them within 8 hours by another means of transport. This takes account of the fact that certain destinations may have a flight distance of less than 1,000 km, but the connection by land is more expensive (e.g. destinations in the UK).

Exception: All destinations within Germany are considered exceptions. This also applies to journeys that take longer than 8 hours by another means of transport. Air travel is generally excluded as a means of transportation for domestic trips.

Compliance with the short-haul regulation is primarily your own responsibility. Of course (depending on the approval procedure), supervisors are required to ensure compliance with the criteria of the travel policy when approving the trip. Ultimately, however, we ask you to take the requirements of the travel policy into account yourself. It should be added that, fortunately, for the vast majority of travelers, the criteria set out in the travel policy are already common practice and taken for granted.

You can use the above criteria as a guide:

• You can reach the destination within 8 hours by another means of transportation, or
• The journey is made within Germany.

In most cases, you can use the regular Deutsche Bahn Navigator to check the travel time by train. There you also have the option of defining requirements for transfer times. As long as these are within reasonable limits, they are included in the assessed travel time.

To check the travel time by car, you can use the established map and navigation services.

Travel within Germany should generally not be carried out by airplane. An exception to this rule is only possible in certain exceptional cases. These include health reasons or the fulfillment of compelling family obligations. Please have exceptions authorised by the Vice President for Administration and Finance (VP-V) in advance.

The Lower Saxony Travel Expenses Ordinance (NRKVO) does not explicitly stipulate that air travel MUST be used if the train ticket is more expensive. On the contrary, travel by air is generally subject to justification. In practice, however, it has been shown that questions can sometimes arise when billing for exceptionally long train journeys. You can avoid this if you briefly check with the travel expense accountant before booking the more expensive trip that your travel expenses can be reimbursed in full. If your travel expenses are funded by a third-party project, a brief consultation with the funding body will also help to ensure that the expenses comply with the requirements of the funding guidelines.

The Lower Saxony Travel Expenses Ordinance does not stipulate any obligation to use airplanes. In principle, the University of Oldenburg strives to avoid or reduce air travel as much as possible with the guideline for climate-friendly business trips.

As long as the planned transfer times and buffers are within reasonable limits, they can be included in the planned travel time.

Most journeys by train or public transport can now be easily planned and booked using the Deutsche Bahn connection search function or other navigation systems. Destinations in other European countries, especially larger cities, can now often be conveniently booked via Deutsche Bahn.

Things can become more complicated when traveling abroad to smaller towns or remote destinations and other means of transport have to be booked in addition to the train, such as local buses.

A number of platforms and websites have been compiled on the travel policy website to help with this.

It is well known that Deutsche Bahn is not always the most reliable mobility partner at the moment. Nevertheless, the threat posed by the climate crisis is just as real and requires decisive action. Rail is an adequate alternative for the distances regulated in the directive.

The travel policy provides for defined circumstances in which an exception to the short-haul regulation can be made:

• Carrying out compelling family obligations, or
• health reasons.

Please have exceptions authorised by the Vice President for Administration and Finance (VP-V) in advance.

In the travel policy, we refer to the statutory CO₂ price. This is set out in Section 10 of the German Fuel Emissions Trading Act (BEHG) and amounts to €55 per tonne in 2025. According to the current legal status, this price is set to rise in the coming years.

There are several reasons for the introduction of the CO₂ charge:

1. Compensation for climate-damaging subsidies
2. Reflection of the real costs of air travel
3. Price control as an instrument for reducing air travel

It is still the case that air travel receives tax concessions from the state which, for example, enables them to offer their services at a lower price. This naturally provides an incentive for many people and institutions to travel by air. In addition, the damage caused by the climate impact of air travel causes real damage to society, for which the airlines then do not pay. These costs are actually paid for by the general public. This effect is called externalized costs. Of course, the University of Oldenburg's CO₂ charge can do little about this, but it does try to offset this effect at least somewhat.

In order to determine the CO₂ charge, you are requested to complete the form Supplement to the  emissions calculation and the amount of the CO₂ charge for air travel and submit it with the statement of your business trip. On this form, you provide information about your flight and determine the amount of the CO₂ charge. The procedure for this is explained on the supplementary sheet. The process of debiting the CO₂ charge is then carried out by the administration.

Transfers from your cost and finance center to the climate protection fund are always made automatically on a quarterly basis, based on your details from the statement.

In individual cases, you would have to clarify this with the funding providers. However, it can generally be assumed that it is not possible to transfer funding to an internal climate protection fund. In such cases, the CO2 charge must be paid from other budget funds. For this purpose, you will find a field on the supplementary sheet for the CO2 charge in which you must enter an alternative cost and funding center. For example, this could be a different funding agency for your working group. Please note that in these cases an additional confirmation must be provided by the person responsible for the funding office.

If business trips are financed from third-party and special funds and no internal financial climate protection contribution can be settled via these funds, this must be financed from the allocated budget of the respective area and the budget funds center associated with the area ("HH" or "EMS" fund) is debited.

The procedure for calculating the CO₂ charge is also explained in the Supplement to the emissions calculation and the amount of the CO2 charge for air travel.

First you need to determine the amount of the climate impact of your flight. To do this, please use the atmosfair emissions calculator. You can access it via this link. Please enter the key data of your flight in the input mask on the website. Please do this as accurately as possible. In addition to the departure and destination airports, you should also enter all stopovers, if you have made any on your journey. Other details, e.g. the type of flight, are optional. The website will then display the amount of climate impact in kg CO₂. Please enter this on the supplementary sheet for the emissions calculation.

To calculate the CO₂ charge, multiply the climate impact by the CO₂ price. This amounts to €55 per tonne in 2025 (= €0.055/kg).

If your flight is a short-haul flight (i.e. a flight distance of less than 1,000 km), an additional base amount of €50 is added to the multiplied value.

Short-haul flights in particular (flights of up to 1,000 km) are (somewhat) avoidable compared to long-haul flights because the distance can be covered by other means of transport. At the same time, the CO₂ charge for these distances is too low to develop a control mechanism. Therefore, flights that cover a distance of less than 1,000 km are subject to the additional base amount.

The funds from the CO₂ charge are transferred into a central climate protection fund. This is used to implement climate protection and sustainability projects at the university. The specific uses will be discussed with the participation of university members. A workshop will be held for this purpose in 2025. The invitation will be sent out in good time.

By matching all CO₂ charges paid, the Presidential Board wants to prevent the impression that the CO₂ charge is a kind of "punitive tax" for research areas that are more flight-intensive than others. The success of the measures from the travel policy is measured and monitored by the university's climate protection management. Should the matching of the CO₂ charges prove to be a false incentive over time, this aspect will be put to the test once again. In addition, the doubling is intended to increase the effectiveness of the climate action fund.

After coordinating with the Finance Department on the legal bases for the CO₂ charge, we have come to the conclusion that the charge will be introduced in 2025 with the legally set CO₂ price of €55 per tonne. The effect of this measure will be regularly evaluated by the university's climate protection management team so that adjustments can be made if necessary. The Fuel Emissions Trading Act (BEHG), in which the CO₂ charge is enshrined in law, also provides for an annual increase in the CO₂ price.

However, anyone wishing to apply a higher CO₂ price when calculating their own CO₂ charge for a business trip by plane can of course still do so.

We regret that the CO₂ charge at this time cannot be processed using the data already available from the previous billing procedure. User-friendliness has always been an important criterion for us when implementing the travel policy in a suitable administrative procedure. We hope that the supplementary sheet developed will be easy to process under the circumstances. We ourselves hope that the procedure for digital invoicing of business trips will be introduced and that this will simplify the collection of the CO₂ charge.

Achieving climate neutrality and the associated reduction in flight emissions during business trips is a key objective of the university. The small additional expense in the billing process is hopefully justifiable on the way to achieving this goal.

With the adoption of the travel policy, the climate action fund is also introduced. Initially, the fund will be financed solely from the CO₂ charge and doubled by the matching of the Presidential Board.

The climate action fund is used to finance climate action and sustainability projects directly at the university. A public university workshop will be held in 2025 on the use of the funds for 2025, where specific projects and measures can be developed.

A public university workshop will be held in for the use of the 2025 funds, where specific projects and measures can be developed. Only then, after a presentation in the Senate, will the use of the funds be determined by the Presidential Board with a resolution. In this way, we want to give university members, especially employees, the opportunity to help shape the use of the funds. The results of this participation process will be made public on the Climate Action Management website.

The use of funds from the climate action fund will be presented transparently on the climate action management website. In spring 2025, once the participation process has been completed, the selected projects will be listed here on the website. At the beginning of the following year (therefore 2026), this overview will be supplemented by the total amount of the CO₂ charges paid into the fund.

For 2025, we are assuming an amount of just under € 120,000. This amount is based on the evaluated travel data from 2023, which already takes into account the base amount for short-haul flights and the doubling by the Presidential Board.

The term includes bus, rail, walking and cycling. In practice, the term public transport is often used synonymously. However, this is not entirely correct in terms of content, as public transportation can also include airplanes and, above all, is distinct from private transportation under property law. The term "environmental alliance" refers to sustainable public transportation and includes environmentally friendly private transportation such as bicycles.

The term planetary boundaries is a scientific term used in sustainability research. "Planetary boundaries are defined for the nine biophysical systems and processes that regulate the functioning of life-support systems on Earth and thus ultimately determine the stability and resilience of the Earth system "¹.

The nine planetary boundaries are:

• Climate change,
• Overloading with novel substances,
• depletion of the ozone layer in the stratosphere,
• Aerosol pollution of the atmosphere,
• acidification of the oceans,
• disruption of biogeochemical cycles,
• changes in freshwater systems,
• changes in land use, and ,
• changes in the integrity of the biosphere.

Six of the nine planetary boundaries are currently exceeded. This applies to

• climate change,
• overloading with new substances,
• the change in biogeochemical cycles (nitrogen and phosphorus cycles),
• the change in freshwater systems ("blue" and "green" water),
• the change in land use,
• and the change in the integrity of the biosphere.

"Three of the Planetary Boundaries have been crossed to such an extent that the high-risk area has been reached (climate change, changes in biogeochemical cycles and changes in the integrity of the biosphere). "¹

¹ Potsdam Institute for Climate Research

Primary sources:

• Rockström, Johan, Will Steffen, Kevin Noone, Åsa Persson, F. Stuart Chapin, Eric F. Lambin, Timothy M. Lenton, et al. 2009. 'A Safe Operating Space for Humanity'. Nature 461 (7263): 472-75. https://doi.org/10.1038/461472a.
• Steffen, Will, Katherine Richardson, Johan Rockström, Sarah E. Cornell, Ingo Fetzer, Elena M. Bennett, Reinette Biggs, et al. 2015. 'Planetary Boundaries: Guiding Human Development on a Changing Planet'. Science 347 (6223): 1259855. https://doi.org/10.1126/science.1259855.
• Richardson, Katherine, Will Steffen, Wolfgang Lucht, Jørgen Bendtsen, Sarah E. Cornell, Jonathan F. Donges, Markus Drüke, et al. 2023. 'Earth beyond Six of Nine Planetary Boundaries'. Science Advances 9 (37): eadh2458. https://doi.org/10.1126/sciadv.adh2458.