Sep 27, 2016

Climate Change - The Better Graph on the Wall

Global Surface Temperature since 1880, and temperature
anomalies - Figure One above , A Better Graph
Slow-motion catastrophe in a graph

Empirical scientists are not bottom-line people. They compile data, access, and then offer conclusions supported, conclusions provisional in nature and ever-changing as more data come to light.

Drs. James Hansen and Makiko Sato are investigating the composition and dynamics of Earth's atmosphere using data pointing to climate change. This work comes as Republicans in America take refuge in denial, and a collective burying of heads in the sand.

It happens the phenomenon Hansen, Sato and colleagues are looking at bears on the fate of life on Earth. They probe the causes and dynamics of global warming, climatic forcings, and in a separate realm quantify global temperatures.

Hansen and Sato offer humanity a new graph accessible to the most foolish, coming six weeks after Hansen called for nuclear power with its attendant hazards and anomalous release of radiation, to replace the energy-production disaster Homo Sapiens imposed on the planet. (This critical nuclear power piece was widely ignored but suggests how dire conditions are in Earth's atmosphere.)

I wrote Dr. Hansen asking for a definitive public conclusion that catastrophic climate change is irreversible, and we as a planet are beyond the point of no return from major life-altering qualities of Earth.

Scientists have little use for making such statements, it's outside the scope of their enterprise, and Hansen and Sato are as likely as not buried in writing their next paper.

Below is a graph including a best estimate showing the projected change in global surface temperatures that is alarming and devoid of adjectives.

That we are beyond the point of no return appears a conclusion supported by the evidence, and mitigation through coordinated geo-engineering is the needed project universal-in-scale, hence a mere conceit.

Hansen and Sato publish this graph showing annual global surface temperatures relative to 1880-1920, illustrating the anomaly, (change and deviation from 'normal', expected values), in global surface temperature the last several decades.

We live in anomalous times.

As carbon and methane emissions are the primary cause for the increase in temperature change and no change in emissions are expected, we can predict values represented in the graph will move upwards and not down.

Here's the new graph, followed by Hansen and Sato's explanation why this graph is instructive to the matters at hand, (a simple 'we're fucked' would have been revealing too as the rate of temperature change looks to be increasing with higher annual temperatures):

Global Surface Temperature since 1880, and temperature anomalies
Figure One, A Better Graph

Fig. 1. Global surface temperature relative to 1880-1920 based on GISTEMP analysis (mostly NOAA data sources, as described by Hansen, J., R. Ruedy, M. Sato, and K. Lo, 2010: Global surface temperature change. Rev. Geophys., 48, RG4004. We suggest in an upcoming paper that the temperature in 1940-45 is exaggerated because of data inhomogeneity in WW II. Linear-fit to temperature since 1970 yields present temperature of 1.06°C, which is perhaps our best estimate of warming since the preindustrial period.

A Better Graph

by Web Team | September 26, 2016
Category: Blog

A Better Graph

26 September 2016

James Hansen and Makiko Sato

Sorry to have temporarily stopped writing Communications – was working on a paper that we hope to soon make available. But here is something useful: a better graph.

For decades we have reported/updated the global temperature record, showing the calendar-year annual-mean temperature, usually with the 5-year running-mean included. I submit that the graph below is not only more beautiful, but more informative and it can be usefully updated every month rather than once a year.  The 12-month running-mean takes out the seasonal cycle just as well as the calendar-year mean and includes the calendar-year mean (black squares).  The 11-year running mean does a pretty good job of taking out solar cycle variability and shorter-term variability such as the Southern Oscillation.

Note that the calendar-year means tend to fall a bit below a preceding maximum in the 12-month running mean, so the 2016 mean will probably fall a bit below the current +1.3°C warming relative to 1880-1920. That small drop is usually related to the phasing of the El Nino cycle relative to the calendar year.

BTW, this graph also switches to 1880-1920 as a base period, because of the widespread interest in the magnitude of warming relative to pre-industrial time. Alternatively, one might argue for an earlier base period, say 1700-1800, but the data are much poorer then and the difference in global mean is only about +0.1°C ± 0.1°C (1880-1920 slightly warmer than 1700-1800), so it is of no practical importance.

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