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Sea surface temperature (SST) observations in the North Atlantic since 1870 reveal a region of enhanced warming off the northeastern coast of North America, and a region of cooling to the south of Greenland. It has been hypothesized that these adjacent SST trends are a result of long‐term changes in the buoyancy‐driven ocean circulation—a slowdown of the Atlantic Meridional Overturning Circulation. The impacts of these historical SST trends on the atmosphere are estimated using idealized atmospheric general circulation model experiments in which the global atmosphere is exposed to modern climatological forcing minus the aforementioned regional SST trends. The local response includes a negative North Atlantic Oscillation tendency and southward shift of the wind forcing for the subtropical gyre. Due to planetary wave propagation, the regional SST trends also induce a northward shift of the intertropical convergence zone over the Indian Ocean. Implications for climate feedbacks and projections are discussed. Plain Language Summary: The ocean surface is warming over most of the planet, with a couple of notable exceptions. One is over the North Atlantic Ocean, just south of Greenland, where the temperature of the ocean surface has actually been cooling by about 1°C since 1870. Nearby, extending off the northeastern coastline of North America is a region where the ocean surface has been warming much faster than the global ocean on average—by about 1.5°C since 1870. This side‐by‐side pair of accelerated warming and cooling trends is likely due to a slowdown of the ocean's overturning circulation, which carries large amounts of heat energy from the tropics toward the poles. This paper reveals the effects of those unusual ocean temperature trends in the North Atlantic on the atmospheric circulation using a computer model of the global atmosphere. The model simulations indicate that these ocean temperature trends are causing shifts in the jet stream, changing the way the winds propel the upper ocean currents, and even have impacts quite far away by moving the tropical rain belt northward in the Indian Ocean. Key Points: The impact of historical sea surface temperature trends in the North Atlantic since 1870 is simulated with a global atmospheric modelAdjacent warming and cooling trends in the North Atlantic Ocean induce a negative NAO‐like response and southward‐shifted gyre forcingPropagation of planetary waves away from the North Atlantic induces a northward‐shifted intertropical convergence zone in the Indian Ocean [ABSTRACT FROM AUTHOR]

ABSTRACT Research on Quaternary climate change is reviewed from the perspective of the real or potential contribution to improving our ability to predict the climate of the future. For convenience the literature is divided into four timescales: orbital, sub-Milankovitch, Holocene and the last 2000 years. Four 'challenges' provide a framework for discussion: better understanding of the way the climate system works, better forecasting of the drivers of climate change, improved estimates of climate sensitivity (change in global mean annual temperature per unit increase in forcing) and evaluation of the models used to predict the climate of the future. Although a great deal of progress has been made, it is concluded that there are some aspects of our scientific culture that limit our potential. These include our tradition of storytelling rather than critical hypothesis testing, an over-emphasis on the role of surface water sinking in the far north Atlantic as a driver of ocean circulation and an attendant under-emphasis on the critical importance of changes in atmospheric circulation, and a lack of rigour in testing the hypothesis that changes in solar irradiance are an important driver of climate change. [ABSTRACT FROM AUTHOR]