2 Introduction

Since the beginning of our civilization up to the present-day humans have developed ways to transport people and goods. In fact, our current way of life depends entirely of transport, and the main and best mean of cargo transport for long distances has been the maritime transport, which now represents 80% of the global trade by volume and 70% of the global trade by value (UNCTAD, 2020). More than any other region on our planet, Archipelagos are totally dependent of maritime transportation for its socioeconomic development, since the need of import and export of goods is even more evident, and many of its inhabitants need to travel around or out of the islands due to a wide range of reasons. Hence, having a well-connected maritime transport system is vital for its development and subsistence. Moreover, a good transport system allows accessibility and mobility, not only for its inhabitants, but also for the transport of goods, which has a great impact in the local economies, thus the more and better the maritime transport logistics are connected, the faster the socioeconomic development (Delgado & Hernández, 2019).

Maritime transport system in remote islands is even more indispensable for competitiveness, thus a maritime logistics efficiency can be determinant in developing trade between two distant regions. For instance, Indonesia has been improving its maritime logistics, and by 2013 was the largest component of its Gross Domestic Product (GDP) with 12% (Chairullah et al., 2021; World Bank, 2013). In this sense, Canary Islands have developed rapidly thanks to maritime transport, since the islands are a strategic stop for those ships on their way to America, Africa or Asia from Europe, and vice versa (J. Hernández, 1996; Tovar et al., 2014). Currently, Gran Canaria has the fourth most important port in Spain, allowing a great amount of trade between regions.

In addition to connection between islands and continents, inter-island transport plays a key role in keeping its inhabitants connected in a scattered territory. The isolation in archipelagic areas is often linked to loss of opportunities for human development, this social exclusion makes people from further regions not able to be involved in the mainstream society culture and opportunities. For instance, Philippines, as a country made up of 7,641 islands with a population over 100 million people, has marked differences of accessibility to social development between its inhabitants close to large urban centers and those living in the most remote islands (Cao et al., 2017). Canary Islands being at 2000 km from the Spain mainland face the challenge to keep its inhabitants well-connected. There are islands whose only mean of transport with the exterior is by sea. For instance, La Gomera Island not long ago opened its airport, which is a minor airport only for internal regional flights and La Graciosa Island does not have any airport, making them totally dependent of maritime transport. In this context, despite the low number of passengers in certain routes, these must stay open, otherwise its inhabitants could be isolated to the social and cultural diversity that central islands have. Thus, the government subsidizes its permanent inhabitants and also the shipping companies to guarantee mobility on those routes (J. Hernández, 1996).

At present, the main types of maritime transportation used in archipelagos for short distances, have been the Roll on-Roll off (RoRo) and Roll on–Roll off Passenger (RoPax), which is supposed as the most environmentally friendly and energy efficient mode of transport due to the rapid loading and unloading of passengers and goods, since merchandise trailers roll in directly as well as passengers with and without cars. RoRo vessels and terminals are designated for cargo trailers, by contrast RoPax vessels have facilities for both cargo trailers and passengers with and without cars. Both, RoRo and RoPax ships can have bow, stern, and side ramps (e.g. Christodoulou & Woxenius, 2019; Marzano et al., 2020).

The disruption of inter-island maritime traffic can have a broad range of socioeconomic impacts, which can vary from not being able to attend a family or a work meeting, to the disruption on the supply chain that can cause a shortage of products, leaving an entire population vulnerable (e.g. Wilson, 2007). In the particular case of Canary Islands, maritime traffic disruptions may have an affect even more drastic, since the development of the islands is mainly based on tourism economy, so that every hour of delay or suspension of a scheduled travel may result in the loss of hundreds of euros. Furthermore, this fact may be even more severe depending on the traffic density of a given route (Mendoza & López, 2002).

In Canary Islands, in 2019, there were 11.8 million of travelers by sea, not including cruise ship travelers, but only those from the companies that have regular routes in the archipelago. Besides, were transported 3.2 million of vehicles in the islands (Puertos Canarios, 2021; Puertos del Estado, 2021). The frequency of routes among the islands varies depending mainly on demand, population, and port infrastructure (J. Hernández, 2018; Puertos del Estado, 2021).

Last decades, the archipelago has experienced a vertiginous growth of population, especially from 2000 to 2010, reaching in 2019 over two million people. According to the canarian institute of statistics, 82% of the population is concentrated in two islands: Gran Canaria and Tenerife. The remaining 15% is distributed among Lanzarote, La Palma, and Fuerteventura, and only 2% between La Gomera and El Hierro (ISTAC, 2021). One of explanations of the concentration mentioned in the two islands is that many families have members in more than one island, this can be observed on the quantity of people born in other islands other than their parents, which has allowed the central islands to develop more quickly due to the greater ease of transporting to the other islands (J. Hernández, 1996).

Something similar happens with the Gross Domestic Product (GDP) among the islands, reaching around € 47 billion in 2019 before the general collapse due to Covid-19. This GDP is highly concentrated, as the population, in two islands: Gran Canaria and Tenerife. The rapid change in economic activities from primary sector to the service sector, has pushed the mobility among the islands. In 2019, the total number of tourists was 15.1 million, 66% of them went primarily to Gran Canaria and Tenerife. Therefore, tourism share of GDP in the Canary Islands was around 32% (€ 15.09 billion), moreover tourism sector is the main supplier of work, its share reaches the 40% of total employ, being the daily average estimate spending by a tourist € 148 (ISTAC, 2021). This reflects that the tourism industry is crucial to the development of the islands. Some of this share contributes to other sectors, increasing the income per capita in the islands (€ 21 244 in 2019). With respect to the transport of goods around the islands, in 2019, 39.7 million tons were transported by sea versus 42 thousand tons by air (ISTAC, 2021). On the other hand, competition for tourists between air and maritime transport companies does not happen with transport of goods, being almost all freight transport done by sea (J. Hernández, 1996).

In view of the above comments, it is clear that the interruption, cancellation, or delay of maritime traffic between islands has important socioeconomic repercussions. Maritime traffic disruptions can be due to a wide range of factors, such as meteoceanic conditions (waves storms and strong winds), port closures, administration closures, human errors, ship malfunction and others. Shipping companies may decide not to operate if there is any risk to the ship, which are tied to the insurance limits, if maneuverability for port operations or while seakeeping is reduced and, in particular, when passenger comfort is considerably affected by meteoceanic conditions. Bad weather conditions can affect ships, which can withstand them depending on their features, in general the bigger the overall length and beam are, the less it will affect the vessel. A common practice in marine navigation to avoid adverse meteoceanic conditions is to plan the route to follow in advance to the travel, as well as receiving meteorologic information to adapt the course to current conditions. However due to short distances between the routes in Canary Islands, this practice has strong constraints, so that in many cases the only viable option is the cancellation of scheduled trips. This work is concentrated only in the maritime disruptions due to strong wind and/or wave conditions.

In this framework, the aim of this study is two-sided. At one hand, the study aims to identify meteoceanic conditions inducing disruptions of maritime transport of passengers and goods between islands in Las Palmas province, exploring its frequency and time patterns. An additional goal is to conduct a preliminary economic impact assessment in terms of the delay, suspension, or detour to alternative ports of maritime regular traffic. Thus, the study is organized as follows: section 2 describes the main features of the study area and used datasets. The methodology used along the study is briefly explained in section 3. Results obtained in the study and their discussion are presented in section 4. Finally, main conclusions are remarked in section 5.