Today we had to collect washed up seaweeds for a craft workshop on seaweed pressing. We love the pressing process as a way to engage people with seaweeds. The day is perfect and I had more time than I usually do to collect. The seaweeds best for pressing are red seaweed that tend to grow at the bottom or below the intertidal zone. When they become dislodged from their holdfasts, dying, they wash up. A northerly wind blew from the land, making the nearshore water calm – it was bliss. Over the last half a year we have been trying to learn a little how to interpret these beautiful satellite images of familiar landmasses and unfamiliar cloudmasses, not often sure what exactly we are looking at. One thing has been certain over the last few months- it’s been mostly warm and dry. We have seen many clear outlines of the cornish coast send down to us via audio file from the satellites. It feels sadly fitting to have spent these months with our ground station, thinking more about weather, whilst the coast our work focuses on is current experiencing the warmest heat waves since records began. Throughout April and May we have seen an ‘unprecedented’ marine heatwave in the northeastern Atlantic. The Met Office has described this heatwave as being unusual in its intensity and persistence. The last time this was observed was in 2023, at the time the most severe marine heatwave recorded in this part of the ocean. Then, both Ruth and I were working harvesting seaweed at every low tide on The Lizard peninsular. Unaware of the data being gathered that summer, we anecdotally saw a large bleaching and dieback of our favourite seaweed Dulse. We worried about its recovery after this local marine heatwave and we wondered what data was being gathered on the effect of heat on the very shallow waters of the intertide. The Dulse seemed to recover well but we couldn’t help wonder how many of these events the ecosystem could withstand. Now working less physically close to this ecosystem, seeing more extreme marine heatwaves, we are left even more concerned for their future. Today, whilst the tide is metres above most species, I swim in the unseasonably warm waters and gather dead floating seaweeds, a tool to teach people about the ecosystem. I wonder how many of them have died prematurely due to heat or if this is just the normal natural lifecycle.

It’s forecast to be an astrological 0m tide in Falmouth – one of the lowest of the year. These extreme tides always sit relatively close to the equinox and, with the high pressure, the tides will creep even lower than expected. We clear the day and head to one of our favourite spots on The Lizard peninsular. This spot is very familiar to us, a tidal pool that offers calm water even when the sea is choppy and rough. The breeze today disrupts the sea and a swell is hitting this part of the coast – we find the pool to be the sanctuary we always hope it to be. Spring brings beautiful rock pooling – no seaweed has become large enough to swamp out other species, most are in their main growing season, so there is lots of beautiful fresh fronds. The sun-bleaching we see later in the year, as the temperature and UV increase, hasn’t yet happened. The water is still cool, not warm enough to support many fouling organisms. The results are clear diverse healthy-looking rock pools. Kelp semi-drys splayed over rocks, waiting to be freed by the incoming tide. Ruth, inspired, partially dries her Sea Lettuce harvest on a bolder. This sky is so blue, with just the wispiest clouds high above – a blue that makes any other weather seem implausible. On this little spot of coast its hard to belief there will be any visible weather systems on the image we receive today,- but there is lots, you can see The Lizard though, sitting under a pool of clear sky. We were here on the equivalent low tide in 2024, the 12 March. It was so cold we had to bring flasks of tea, hats, gloves and thermals so we could last a few hours out here. Today we bath in the sun, agreeing, with relief, that we’ve made it through winter. Sometimes on days like this we do surveys and try to document what we see – today we just enjoy the space. We wonder how we can incorporate more days like this back into our lives. The Seaweed Institute