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Rip currents ("rips") are the leading cause of drowning on surf beaches worldwide. A major contributing factor is that many beachgoers are unable to identify rip currents. Previous research has attempted to quantify beachgoers' rip identification ability using photographs of rip currents without identifying whether this usefully translates into an ability to identify a rip current in situ at the beach. This study is the first to compare beachgoers ability to identify rip currents in photographs and in situ at a beach in New Zealand (Muriwai Beach) where a channel rip current was present. Only 22 % of respondents were able to identify the in situ rip current. The highest rates of success were for males (33 %), New Zealand residents (25 %), and local beach users (29 %). Of all respondents who were successful at identifying the rip current in situ, 62 % were active surfers/bodyboarders, and 28 % were active beach swimmers. Of the respondents who were able to identify a rip current in two photographs, only 34 % were able to translate this into a successful in situ rip identification, which suggests that the ability to identify rip currents by beachgoers is worse than reported by previous studies involving photographs. This study highlights the difficulty of successfully identifying a rip current in reality and that photographs are not necessarily a useful means of teaching individuals to identify rip currents. It advocates for the use of more immersive and realistic education strategies, such as the use of virtual reality headsets showing moving imagery (videos) of rip currents in order to improve rip identification ability. [ABSTRACT FROM AUTHOR]

Rip currents (rips) are the leading cause of drowning on surf beaches worldwide. A major contributing factor is that many beachgoers are unable to identify rip currents. Previous research has attempted to quantify beachgoers' rip spotting ability using photographs of rip currents, without identifying whether this usefully translates into an ability to spot a rip current in situ at the beach. This study is the first to compare beachgoers ability to spot rip currents in photographs and in situ at a beach in New Zealand (Muriwai Beach) where a channel rip current was present. Only 22% of respondents were able to identify the in situ rip current. The highest rates of success were for males (33%), New Zealand residents (25%), and local beach users (29%). Of all respondents who were successful at identifying the rip current in situ, 62% were active surfers/bodyboarders and 28% were active beach swimmers. Of the respondents who were able to identify a rip current in two photographs, only 34% were unable to translate this into a successful in situ rip identification, which suggests that the ability to identify rip currents by beachgoers is worse than reported by previous studies involving photographs. This study highlights the difficulty of successfully identifying a rip current in reality and that photographs are not necessarily a useful means of teaching individuals to spot rip currents. It advocates for the use of more immersive and realistic education strategies, such as the use of virtual reality headsets showing moving imagery (videos) of rip currents in order to improve rip spotting ability. [ABSTRACT FROM AUTHOR]

Bryan, K.R..; Davies-Campbell, J.; Hume, T.M., and Gallop, S.L., 2019. The influence of sand bar morphology on surfing amenity at New Zealand beach breaks. In: Bryan, K.R. and Atkin, E.A. (eds.), Surf Break Management in Aotearoa New Zealand. Journal of Coastal Research, Special Issue No. 87, pp. 44-54. Coconut Creek (Florida), ISSN 0749-0208. Wave breaking patterns on many of New Zealand's prominent surfing beaches are controlled by surf zone sand bar morphology. In turn, sand bars change in response to wave breaking and surf zone current patterns, with well-known theories predicting more linear bars during winter, and more three dimensional patterns during lower energy conditions. Here four databases of sand bar morphology from New Zealand, collected at Aramoana, Piha, Lyall Bay, and Tairua, are analysed to detect changes in key parameters that control wave surfability: the length and orientation of the bar. Longer bars provide the potential for longer surfing rides, whereas the orientation determines the peel angle or the difficulty of the ride. Computer algorithms were used to detect sandbars from light intensity maxima patterns obtained from averaged, geo-rectified video imagery collected at each beach. The length of bar was inversely correlated with orientation, with longer beaches also having longer bars. Sand bar length and orientation was highly variable, both spatially (with location along the beach) and temporally (seasonal and interannual variability), making it difficult to detect any significant changes between location or with time. However, sand bars were generally shorter and more obliquely-oriented near the ends of these headland-enclosed beaches. Although no significant seasonal variations were detected, there were detectable interannual variations on the two beaches with the longest datasets, which were correlated with the Southern Oscillation Index. Implications of the study are that, unless changes are substantial such as caused by groins and seawalls, long monitoring datasets are needed to detect anthropogenic impacts on surf breaks. [ABSTRACT FROM AUTHOR]

Gallop, S.L.; Bryan, K.R.; Pitman, S.J.; Ranasinghe, R., and Sandwell, D., 2016. Pulsations in surf zone currents on a high energy mesotidal beach in New Zealand. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 378-382. Coconut Creek (Florida), ISSN 0749-0208. The exchange of material between the surf zone and continental shelf can be driven by pulsations in rip current velocities. However, there is a poor understanding of the relationship of these pulsations to surf zone morphology and material exchange. Moreover, understanding of rip current dynamics has focused mainly on single-barred beaches in an intermediate state, and there have been few studies on high energy beaches. Therefore, this paper undertakes preliminary research on surf zone current velocity pulsations, on a high energy beach in New Zealand. This initial analysis presents results from two days of measurements using Acoustic Doppler Velocimeters and Lagrangian GPS drifters. Drifters revealed pulsations in current velocities on the order of ∼0.5-2 m s−1 throughout the surf zone, whether inside a rip current circulation cell or not. More infragravity wave energy was associated with constant pulsations in current velocity, and lower infragravity energy with pulsation bursts, lasting 5-10 minutes, interspersed with periods of relatively constant velocity lasting 15-25 minutes. However, higher wave conditions also reduced the exit rate from the surf zone. [ABSTRACT FROM AUTHOR]