## 3 Results and Discussion
### Discussion
In many contexts, particularly in countries with strong regional or local competences, the absence of effective intergovernmental cooperation mechanisms has led to fragmented or redundant efforts, as observed in Spain, for example. A particularly relevant trend is the divergence in adaptive capacity between Northern and Southern Europe. This gap arises from multiple interrelated factors. Northern countries such as Germany, the Netherlands, and the Scandinavian states tend to have greater financial and technological capacities to implement advanced solutions (e.g., infrastructures or early warning systems), whereas many Southern countries face more severe budgetary constraints. Moreover, Southern Europe is more exposed to extreme events such as droughts, biodiversity loss, and sea level rise, factors that increase both the urgency and the complexity of effective adaptation responses [8; 36]. Many of these measures are interconnected and can be classified into several categories, such as the development of early warning and monitoring systems or the implementation of planned retreat or relocation strategies [12]. The vast majority of measures are flexible in nature, and this allows for their abandonment without incurring significant financial costs, with exceptions being engineering and service measures [12]. Among the physical-structural solutions, ecosystem-based and engineering measures are the most common. This is because coastal ecosystems are particularly vulnerable to climate change and human activities, in addition to the multiple benefits they provide for human well-being. In this sense, more than half of European countries have integrated this approach into their adaptation plans. Notable exceptions are Croatia, Greece, and Lithuania. As far as engineering measures are concerned, there is a gradual shift towards more sustainable approaches. The increased use and understanding of the coast means that this adaptation subtype is the most commonly considered in regulatory instruments, although it is not equally observed across all countries. This trend contrasts with traditional coastal management paradigms. Traditionally, a fixed coastline was assumed, and hard or \"gray\" infrastructure, such as dikes and seawalls, was employed to prevent flooding and erosion. These measures predominated during the 20 th century in Spain, Portugal, and even the Netherlands, where 15% of the coastline consists of dikes and other artificial marine barriers [25; 43; 59]. However, these measures do not provide a reliable long-term solution, as they can increase erosion in adjacent areas, affect the seabed, and reduce the natural capacity to respond to changing conditions [12]. In Portugal, these types of infrastructure have been observed to drive urban expansion and occupation of marginal areas as they generate a false sense of security [26]. In Belgium, the Sigma Plan is a project that combines the use of dikes with controlled flooding areas. This plan was updated in 2005 to consider future climate change scenarios. The Sigma Plan currently incorporates additional measures for the years beyond 2050 in anticipation of further sea level rises. In recent years, however, these solutions have given way to \"soft\" interventions that provide economic and social benefits, such as beach regeneration and dredging [20]. Although these measures allow the coast to respond dynamically to change, they are merely temporary responses [60]. In recent studies, it was found that these interventions have modified beaches since 1950 and altered the coastal landscape in Lithuania [61; 62]. The transition to a new approach that combines gray-green coastal protection has become a priority on the north Norfolk coast (UK). This coastline consists of various habitats:freshwater, brackish, and intertidal wetlands; beaches; and dunes. More than 100,000 people reside along the 40 km of coastline between Hunstanton and Weybourne, and this region faces flood and erosion risks.