New Revelations on Climate Change

It is not me who will present new revelations on climate change. Instead, these are made by those who still deny that climate change is man-made. Here are a few examples:

Tweet on November 6, 2012.

Mr. Walker, are we really doing the best we can? Let's consider the rise in global temperature.

Warnings already in 1988

In 2007, I delivered a talk at the Freiburg-Madison-Gesellschaft titled "Gaia schlägt zurück." The Revenge of Gaia was the title of a book by James Lovelock. I also used the 2007 IPCC report, Climate Change: The Physical Science Basis, to support my talk. The following graphic is drawn from there.
*Intergovernmental Panel on Climate Change

The IPCC's 2007 projection shows a 0.47 °C rise in global temperature between 2000 and 2020. Over that short period, the increase is nearly independent of the various CO₂-emission scenarios assumed by the IPCC. Thirteen years later, we measured temperature data.

©Wikipedia

The measured global temperature rise between 2000 and 2020 is 0.48 °C; the projected rise is within the margin of error. Does this mean there is no problem?

In 2017, the measured temperature exceeded the long-term mean temperature averaged from 1880 to 2017 at every location.

Mauna Loa in Hawaii is not perturbed by civilizing influences
and used as the Earth's reference point.

What is most disturbing is the increase in global CO₂ concentration over the years, with no sign of leveling off. Where are the sources of greenhouse gases?

©Wikipedia

In recent years, decreases in carbon dioxide emissions in the United States and the EU have been more than offset by fossil fuel combustion in China and India. In particular, international shipping and aviation increased greenhouse gas emissions.

In Germany, CO₂ emissions follow the European trend of a slight decrease. In particular, households acquired more energy-efficient machines and LED lighting. Although nuclear power is phased out, energy production has become less CO₂-prone since inefficient lignite-burning power stations were shut down. At the same time, the contribution of wind and solar power to the energy mix increased. Only transport is identified as the Achilles heel, with more people driving SUVs.

In Germany, we are far from our CO₂ emission targets. The decrease must become steeper to meet the 2050 Paris target.

Deniers of human-caused global warming seek alternative explanations for observed climate change. Here are slides taken from an ARD presentation on television showing how natural and man-made factors may influence the observed temperature rise:

Observed temperature increase with time vs. solar activity

Influence of the Earth's orbital parameters on temperature rise

The impact of volcanic activity

Human-made ozone layer

Deforestations

Smog and aerosols in the atmosphere have a cooling effect.

Greenhouse gases have the most significant effect on rising temperatures.

All natural and human-made factors combined give a "perfect" fit to the measured data.

One consequence of rising temperatures is the loss of ice in glaciers and polar regions.

According to the IPCC, projected sea-level rise from ice melt ranges from 2 mm/year under climate protection measures to 17 mm/year without CPM.

The measured rate of sea-level increase is actually 3.3 mm/year.

Pictures of the "land underwater" doomsday scenario are well known.

Last May, in a talk about climate change in south-west Germany, Dr. Andreas Becker of the German Weather Service showed the following slides explaining new weather phenomena:

Due to global warming, temperature gradients between polar regions and temperate zones have decreased.

In the summer of 2018

This causes frequent jet stream anomalies, resulting in stable, stationary weather conditions. Thus, heatwaves and periods of drought are modulated by steady rainfall and inundation.

In Germany, from 1881 to 2018, the increase in sunshine duration from April to June was accompanied by a rise in temperature. No long-term deficit in precipitation is observed for the same period, although 2018 was a particular year.

From April to October 2018, a significant anomaly (circled) was noticed in a combination of the lowest precipitation and the highest temperature compared to 1881 to 2018.

Here are the hydrological predictions for Germany. The water balance is the difference between precipitation and evaporation. Due to higher evaporation at higher temperatures, the region around our capital, Berlin, is likely to become a desert.

©BZ

Residents of Freiburg are reminded that summers are becoming hotter. The Menetekel is not written on the wall but painted on a streetcar with colored stripes.

Ultimately, all efforts to limit the rise in global temperature to 1.5 °C* will fail if population growth continues. "Our blue planet is too small for 10 billion people", as State Senator Scott Wagner formulated, "We have more people. You know, humans have warm bodies. So is heat coming off?" Yes, it is around 100 watts per person.
*IPCC Special Report on Global Warming of 1.5 °C  on October 8, 2018 

**