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The Holocene is the Earth's most recent interglacial, which began approximately 11,500 years ago. Environmental change across this interval and the preceding Late Glacial, driven by factors such as orbital forcing and solar variability, can be reconstructed from archives with annually-deposited layers or annual growth layers and through the use of empirical and physical models. The early Holocene climatic optimum was an interval of warmer climate than the present day, and was followed by orbitally-related cooling which began to occur in the last 4,000–3,000 years ago. Over the last c.1200 years, three distinct climate phases are apparent in palaeo-records: the Medieval Warm Period (Ad 800–1300), the Little Ice Age (14th–16th century Ad to Ad 1850), and recent warming since AD 1850. Anthropogenic influence on global ecosystems has increased steadily since the Late Glacial, culminating in a modern-day system for which few analogues for past environments now exist.

Many events in global tectonics and high latitude climate had significant effects on Cenozoic climate evolution. This chapter explores three revolutions in climate research that have dramatically altered our perception of global and African climate. First, the discovery that large magnitude climate events occurred abruptly, sometimes in as little as decades, has prompted high-resolution paleoclimate reconstructions and new conceptions of climate dynamics. Second, recent climate studies have revealed significant tropical climate variability. Modern observational climate data have indicated that the largest mode of global interannual climate variability is the El Niño Southern Oscillation in the tropical Pacific. Revised estimates of tropical sea surface temperatures during global cool and warm events have revealed significant tropical sensitivity to global climate change. Third, the role of the tropics in global climate change has been reconceptualized. This chapter also discusses the modern climate of Africa, abrupt events in the Paleocene, Oligocene Antarctic glaciation and Southern African climate, mid-Miocene climate change in Africa, plio-Pleistocene environmental change, cool and dry conditions during the Last Glacial Maximum, and Holocene climate.

Two related phenomena characterize the last 30,000 years or so of the Pleistocene and the Old Stone Age in Europe, a period known as the Upper Paleolithic. The first of these is the arrival of a version of ourselves, Homo sapiens, around 40,000 years ago. The second is the creative explosion in technology, equipment, raw materials, art, and decoration that took place in this period. There appears to have been a substantial upgrade in human abilities and the variety of activities taking place. The first part of this chapter examines some of the sites and places that tell this story. At the end of the Pleistocene and the Paleolithic, 10,000 years ago, hunter-gatherers continued to thrive in a warmer, “postglacial” Europe, but their time was coming to an end. Agriculture had been invented in the Near East and was spreading toward the continent, arriving in the southeast by 7000 BC and reaching the northeast by 4000 BC. This period of post-Pleistocene hunter-gatherers in Europe is known as the Mesolithic and is the focus of the second part of this chapter. By the end of the Pleistocene, Homo sapiens had created art, invented many new tools, made tailored clothing, started counting, and spread to almost all parts of the world. As noted earlier, the oldest known representatives of anatomically modern humans have been found in East Africa, from almost 200,000 years ago. Further evidence of the activities of these individuals comes from caves around Pinnacle Point on the Cape of Good Hope in South Africa and dates to 165,000 years ago. This evidence is not in the form of fossil skeletons, but artifacts. Several finds—small stone blades, pieces of red ochre (an iron mineral used as a pigment), the earliest known collection and consumption of shellfish—point to new kinds of food, new tools that probably required hafting, and the use of powdered mineral as a pigment or preservative. These are firsts in the archaeological record and likely document the beginnings ative explosion witnessed more fully after 50,000 years ago.

This chapter develops key concepts from climate change science to provide a framework in support of the case studies in climate change archaeology. It considers both natural climate change and climate change driven by increased greenhouse gases (GHGs), so that the contribution of climate change archaeology to the building of the resilience of modern communities can be placed in the appropriate context. It provides an introduction to palaeoclimate research, noting how new methodologies, concepts, and understandings have developed in the last few decades. Next, it critically considers the role and claims of archaeological and palaeoenvironmental research. It presents the most up-to-date palaeoclimate evidence on climate in the deep past, particularly for the period since the Last Glacial Maximum (LGM) c.21,000 years ago. The evidence for human-induced climate change and the scenarios for climate change in the future complete this exploration of climate change research.

As two researchers with significant credibility in the study of early Florida, James S. Dunbar and David K. Thulman evaluate the potential for Paleoindian research on the Southeastern Continental Shelf (SECS) of the U.S. In this chapter, they discuss ways to explore Clovis and pre-Clovis landscapes (or, as they collectively call them, early Paleoindian sites) in the SECS and how researchers might narrow their search and increase their chances of finding Clovis and pre-Clovis sites offshore. In doing so, they complement Halligan’s chapter in this volume (chapter 3) on exploring Florida’s inland waters for submerged sites. They evaluate the strategies available: thoughtful searching for both analogous natural and manmade landforms and serendipity. Of the two, the second approach has arguably produced the most sites so far. Dunbar and Thulman explore the “thermal enclave hypothesis” of Russell et al (2009) and follow David Webb’s earlier work on his idea for a climatically propitious region that could support animals and plants through the Last Glacial Maximum (LGM). Dunbar and Thulman further suggest the possibility of a shellfish/marine adaptation by early-Paleoindian-period colonists. They posit that finding such sites would open new windows into the study on the behaviors of the early Floridians.

Over the North Atlantic the eddy-driven jet stream finally separates from the subtropical jet, forming a split jet structure. Free from the steady influence of the Hadley cell, the northern jet is highly variable and its shifts and meanders affect weather and climate patterns around much of the hemisphere. This chapter introduces the North Atlantic Oscillation, the dominant pattern of jet variability, giving an overview of its history and impacts.