Short answers, pulled from the story.
The Laptev Sea was named on the 27th of June 1935 after Russian Arctic explorers Dmitry Laptev and Khariton Laptev, who first mapped its shores between 1735 and 1740 as part of the Great Northern Expedition. Before that date it had been called the Nordenskjold Sea since 1893, and before that the Icy Sea, Siberian Sea, Lena Sea, and Tartar Sea.
Air temperatures in the Laptev Sea stay below 0 degrees Celsius for eleven months a year in the north and nine months in the south. The average January temperature ranges between -31 and -34 degrees Celsius, with a recorded minimum of -50 degrees Celsius. The highest temperature ever recorded in the region was 32.7 degrees Celsius at Tiksi.
The Laptev Sea exports an average of 483,000 square kilometres of sea ice per year, more than the Barents, Kara, East Siberian, and Chukchi seas combined. The combination of shallow water, extreme cold, and large river inflows creates conditions that generate and export ice in all months except July, August, and September.
The Yukaghirs and their sub-group the Chuvans were the earliest peoples recorded living on the Laptev Sea coast, relying on fishing, hunting, and reindeer husbandry. They were joined by the Evens and Evenks around the 2nd century and later, between the 9th and 15th centuries, by the Yakuts, who had all migrated north from the Lake Baikal region.
Vasili Pronchishchev sailed from Yakutsk in 1735 to survey the Laptev Sea coast and the Taymyr Peninsula. Many crew members died of scurvy during the winter at the Olenyok River mouth. Pronchishchev and his wife both died of scurvy on the return journey in 1736. Maria Pronchishcheva Bay in the Laptev Sea is named after his wife.
The Ust-Lena Nature Reserve was established in 1985 in the delta of the Lena River, covering 14,300 square kilometres. The New Siberian Islands were added to the reserve in 1986. It now hosts 402 plant species, 32 fish species, 109 bird species, and 33 mammal species.