TOU-I-3: Heat stress in spas used for their healthy climate

The picture shows a path lined with tall trees, at the edge of which are benches. A person sits on one of the benches and looks into the adjoining forest landscape.Click to enlarge
Climatic health resorts use climatic factors to cure, alleviate or prevent diseases.
Source: Photograph: © lotharnahler / stock.adobe.com

2019 Monitoring Report on the German Strategy for Adaptation to Climate Change

Table of Contents

 

TOU-I-3: Heat stress in spas used for their healthy climate

In the two periods of 1971–2000 and 1981–2010 the threshold value for heat stress was exceeded in four each of 62 climatic health resorts. The next evaluation will not be available until preparation of the 2023 Monitoring Report.

The number of health resorts exceeding or falling below the threshold value is shown in two stacking columns. There are data for the period 1971 to 2000 and 1981 to 2010. Also shown in the form of dots is the mean number of days above the threshold value in health resorts where the threshold value was exceeded. It was around 24 days from 1971 to 2000 and around 36 days from 1981 to 2010.
TOU-I-3: Heat stress in spas used for their healthy climate

The number of health resorts exceeding or falling below the threshold value is shown in two stacking columns. There are data for the period 1971 to 2000 and 1981 to 2010. Also shown in the form of dots is the mean number of days above the threshold value in health resorts where the threshold value was exceeded. It was around 24 days from 1971 to 2000 and around 36 days from 1981 to 2010.

Source: DWD (health resorts climate assessments)
 

Will spas retain their healthy climate?

Holidays in health resorts (spas) play a major role in German domestic tourism. What these spas can offer is not at all limited only to courses of treatments and rehabilitation measures financed by social insurance agencies: health and wellness vacations are steadily gaining in popularity, and they too are spent in health resorts. In 2017. for example, approximately 40 % of all tourism-related overnight stays in Germany took place in municipalities with the requisite designation, i.e. in health spas, seaside resorts, resorts with healthful climates, also known as climatic health resorts.71 Even in cases where the specific designation or treatments offered are not the decisive factor in overnight stays (e.g. family holidays by the North Sea are probably often influenced by different motivations), the overnight stays in preventative treatment centres and rehabilitation centres nevertheless account for 10 % of all overnight stays nationwide. These centres are particularly dependent on a municipality’s designation as a spa.

All health resorts have in common that they have to meet specific demands including bio-climatic and air quality in order to hold on to their designation. It is essential that the climate prevailing in a specific location can be used for therapeutic purposes. Furthermore, climatic health or sea resorts must be suitable for healing, alleviating or preventing human diseases. In other words, stimulating or benign effects must be available in abundance. The stimuli concerned include e.g. cold stimuli, strong fluctuations in temperature or sudden gusts of wind, while benign factors include e.g. extraordinary purity of the air or thermally balanced conditions. Stress factors which might include low intensity of solar radiation, polluted air or heat stress, would be tolerated in the long term only in minimal amounts. Depending on an individual’s medical condition or physical constitution, therapies make use of stimuli and benign factors prevailing in a healing climate, which allow their body to regenerate but also to toughen up as a protection from illness or disease.

Heat stress is an important consideration in assessing the bio-climatic situation of health resorts. Heat stress arises typically on days in summer weather with light cloud cover, high pressure conditions at high temperatures, high air humidity and light wind. These conditions make it difficult for the body to lose heat; as a result, the body’s own thermoregulation system has to work hard to balance its heat regime and to avoid overheating.

Statistical evaluations of climate data for Germany indicate that days and months which are above-average hot have become more frequent in the course of the 20th century and that extreme heat events are on the increase. As a result of climate change, it is to be expected that in future the frequency and intensity and also the mean temperatures of hot periods will increase further. In the course of this development, the bio-climatic factors in climatic health resorts might change, eventually denying spa guests the healing effects from a local climate, and the climate losing its therapeutic role. In a worst-case scenario this might lead to individual municipalities losing their designations as climatic health resorts.

To enable the assessment of the climate prevailing in climatic health resorts, the number of days causing heat stress over a period of 30 years were examined. The days considered were those on which the threshold value of the Perceived Temperature of approx. 29 °C was exceeded. In climatic health resorts this must not occur on more than 20 days over the long-term average. In the period 1971–2000 the threshold value for heat stress was exceeded in four of 62 climatic health resorts on more than 20 days. The maximum value measured occurred in a municipality with a long-term average of 23.3 days of heat stress. However, the designation has so far not been withdrawn from this municipality.

For the period 1981–2010 the evaluation method was fundamentally revised, and the so-called heat stress day was redefined. This involved on one hand attributing greater importance to the impact of sultry conditions on human health, and on the other, the potential adaptation of human beings to a changing climate was introduced, loosely based on the heat warning system adopted by DWD. A heat-stress day is now classified as a day on which the threshold towards strong heat stress or the threshold to moderate heat stress is exceeded while sultry conditions prevail. Based on this definition, the calculation for the same meteorological time series clearly identifies fewer days with heat stress than in the previous type of evaluation. The new definition also changes the regional distribution. In conducting a statistical examination, it is possible to calculate a location-specific reference value for the number of days with heat stress which broadly follows the 20 days used in the previous period. Despite all the changes, this approach enables the assessment of health resorts also for the period 1981-2010 in continuity with former evaluations.

71 - StBA 2018: Tourismus in Zahlen 2017. Tabelle 2.1 Ankünfte und Übernachtungen in Beherbergungsbetrieben 2017

 

Interfaces

BAU-I-1: Heat stress in urban environments

GE-I-1: Heat exposure and Public awareness