This last month, I have been walking the beach early in the morning from 5:15 to around 6 am. I leave home, meet Palayam anna, a retired fisher, friend and my teacher of #ScienceOfTheSeas. We walk quietly, mostly. On occasion, Palayam would make a wry observation about the sea or about the disappointed fishers that returned with empty nets.
On June 5, the walk began as usual. The sun was showing as an orange pink haze in the horizon as we turned north on the sandy path separating the village from the narrow beach. By the time we reached the northern end of the village – a three-minute walk – the sun was out.
As we neared Adyar estuary, Palayam brought me out of my reverie. “Anna, you are lost in thought. Look around and tell me, where’s the wind blowing from.” With some doubt, as I didn’t want to disappoint the teacher, I replied with a question: “Vaadaya adikkuthunna. Correctaa?” (‘It’s blowing from the north brother, correct?’) My doubt was not without basis. The receding of the northeast monsoon around February is accompanied by a change of current and winds. Where the current and winds flow/blow from the north during Chennai’s dominant monsoon, around February, the current switches and begins flowing from the south. This much I had been taught, shown and was expected to know.
Why then, was the wind blowing into our faces as we walked north? That was my confusion. Palayam then asked me to read the nearshore current. In my earlier lessons, I had been taught that the current follows the wind, that both run in the same direction. The nearshore current – as told by the angle at which the waves approach the shore – indicated that the flow was from south southeast to north, and against the prevalent wind. South east is kachan eeraan in fisher lingo. Kachan is south and eeran is east. The wind had managed to shift the current from nedun kachan (south) to kachan eeran (southeast).
The result was a sea that was rougher than the sea of the day before as the prevailing current collided with the prevailing wind. “Pazhaverkaatla weatheraa irukkum. Vadakkula engaiyo puyal. Nammalukku onnum illai. Ipdiye irunthichunaa, onnu rendu naalula namakkum mazhai vara vaaippu irukku,” he said. ‘The weather is likely to be rougher in Pazhaverkadu (Pulicat). Further north, somewhere there is a storm brewing. Nothing for us. If this persists, who knows we may get a shower in a day or two.’
It is 6 pm on 7 June as I write this. A 20-minute downpour has blessed us. Tomorrow morning, I will speak to Palayam about his diagnosis and prognosis.
Note: The video was taken on June 6, a day after our conversation, as we were walking back. To tell the nearshore current, look at how the surf breaks. If the southern edges break first with a northward roll, the prevailing current is from the south. Fishers from the northern districts of Tamil Nadu refer to this as a thendi karsala (thendi is south and karsala is nearshore current).