Ocean floor deposits and model calculations have confirmed that in the past 3 million years, the global mean temperature has never been more than two degrees above pre-industrial levels, with fluctuating CO2 levels in the atmosphere. Since the beginning of industrialization, more CO2 has accumulated in the atmosphere through the burning of coal, oil and gas than probably ever before in the past 3 million years. Thus, in our current century, there is real threat that without effective climate policy the 2-degree limit of global warming will be breached for the first time – with far-reaching consequences.

Day-to-day variations in temperature, i.e. short-term variability, has a substantial impact on macroeconomic growth, according to an article by Maximilian Kotz et al, published in Nature Climate Change. If this variability increases by one degree Celsius, economic growth is reduced on average by 5 percentage-points. Particularly affected are economies in low-income regions of the global South, where seasonal temperature differences can be as small as 3°C and farmers and small business owners have not yet cultivated resilience against temperature variability. This is in contrast to Economies in Canada or Russia, where average monthly temperature varies by more than 40°C within a year and economic actors seem better prepared to cope with daily temperature fluctuations than in low-latitude regions

Never before in over 1000 years the Gulf Stream System (also known as the Atlantic Meridional Overturning Circulation AMOC), has been as weak as in the last decades. PIK researchers have determined evidence of the AMOC weakening with the help of 11 proxy data series (information gathered by so called climate archives like ocean sediments, corals etc): They have compiled 11 independent data series from the North Atlantic, almost all of them from deep-sea sediment cores. They all provide a consistent picture about the flow characteristics of the Gulf Stream System and its weakening in the past 70 years. The slowdown is likely related to man-made climate change.