Winter is Coming

Ten million more years roll over. 265 million years have now amassed since the beginning. and the early Ultimocene has come to an end. The first fifteen million years of this final era have been a display of beautiful abundance and unmatched biodiversity.

Yet soon this, like all similar good times of the past, will be but a faded memory in the sands of time.

Climate changes which began in increments ten million years ago now comes to a head as the first ice age of the Ultimocene arrives suddenly and violently. A variety of factors contributed to this sudden and drastic shift in global climate, beginning with the weakening of the worlds' volcanic activity over fifteen million years ago. As plate tectonics ceased and volcanism decreased, the carbon cycle was disrupted and less carbon dioxide was released into the atmosphere. Compounding this, the high amount of vegetation both on land and at sea that proliferated briefly in the warm and biodiverse first part of this era resulted in most atmospheric carbon becoming locked up into the soil. The reduction of this important greenhouse gas, vital for maintaining a warm climate, has now set into play a rapid and vicious chain reaction of climate change. The reduction of carbon dioxide levels in the atmosphere mean summers over formerly temperate zones now fail to reach warm enough temperatures to melt the previous winter's snows, which instead become packed down into glaciers as more snow is deposited each winter over thousands of years. As these glaciers expand, they creep further from their polar origins, snuffing out everything they touch. All of these collective factors will continue to transform what was a thriving green world into a harsh expanse of cold-adapted brambles, tundras, and glaciers as far as the eye can see over the next few thousands of years.

Life evolved in myriad forms in the relatively stable previous epoch now plummets from the precipice of a mass extinction both rapid and devastating, the vast majority of all species on Serina with nowhere to go. Hemmed in by cold weather from north and south, the richly biodiverse tropical forests and much of their untold life have already succumbed, displaced by a rapidly cooling climate and a southerly flood of northern organisms seeking refuge. While some of the most adaptable groups manage to adopt new forms and strategies to survive a much colder world, most are displaced without refuge as the weather cools by weary colonists seeking shelter from the former temperate zones. The most extreme global cooling has occurred in just the last one million years, a rate of change that few environments could adapt to. The equatorial regions of Serinarcta, steamy jungles just a few million years ago, are now temperate and the last holdout in which broad-leaf forests can still survive, as a world of jungles becomes a world of open wind-swept plains and tangled cold-hardy thicket. The entire continent of Serinaustra, once abundant with life, is now a nearly lifeless frozen waste larger than Antarctica. Sea ice freezes around both poles and in doing so accelerates the process of freezing by disrupting, then stopping the circulation of warm ocean currents altogether. Rapid polar glaciation, locking water up in huge deposits of ice, has produced a drop in sea levels and expanded the size of the continents, including the formerly small Meridian Islands which have become primarily one large island as the sea levels have reveal the volcanic mountain range that laid beneath. As the sea levels recede, hundreds of islands of every size - formerly sea mounts - have risen out of the shallow seas and breached the surface. Barren at first, some will become new, if short-lived havens for endemic life to evolve in the coming ice age. The climate has become drier again as so much water is frozen and out of the water cycle, with a new cold desert forming in the center of Serinarcta.

Yet for some life, the chilling world is a new opportunity for success. As the land suffers, the sea is thriving. Shallow, cold oceans allows for the growth of enormous stretches of of sea bamboo out from coastal waters and across the entire sea, providing the base of a rich food chain across the global ocean. The freezing of the polar seas and the disruption of warm equatorial-to-polar currents has for the past eight million years resulted in an extremely productive, frigid, and highly turbulent seaway between Serinarcta and Serinaustra, kept churning by an equatorial current that wraps east to west around the globe, maintained by slight differences in the moon's day and night temperatures. This cold, well-oxygenated, churning water brings up massive amounts of sediment and with it nutrients that allow enormous blooms of phytoplankton. Fish and aquatic invertebrates proliferate in incredible abundance, providing an unusually high abundance of food availability for oceanic predators, both large and small. Known as the Icebox Seaway, as the world cools this open channel of seawater becomes the most productive ocean that will ever exist on the world of Serina. The channel between these two landmasses becomes a lifeline not just for marine life, but some of the last forests on land as well. The turbulent waters of the icebox seaway may bring harsh winter storms to adjacent lands, but this equatorial site still attains the mildest temperatures left on the world of birds, enough to still support a thriving temperate forest ecosystem and a remnant refugia - for a little longer - for organisms already extinct elsewhere. It serves for now as a protective barrier for the southern coastlines of Serinarcta, preventing the spread northward of the southern ice cap that already spreads across the southern continent almost entirely, and its existence will keep Serina from becoming entirely iced over during the current ice age.