Monthly Archives: June 2019

Has Himalayan glacier melting doubled?

“A newly comprehensive study shows that melting of Himalayan glaciers caused by rising temperatures has accelerated dramatically since the start of the 21st century,” claims a Ph.D. candidate at Columbia University’s Lamont-Doherty Earth Observatory. Willis Eschenbach shares his thoughtsclick here

Dry summers come and go

“We aren’t the first scientists to confirm this trend,” says Dr. Tobias Scharnweber, one of the authors of the article. “However, what is new in our reconstruction is that we were able to calculate these growth rates using our own data method that we had developed especially for this project. This enabled us to show that average summer rainfall amounts were much lower at the time of the Mediaeval Climate Optimum, i.e. approximately 1000 years ago, than previously presumed. Maybe ‘one-in-a-century’ summers, like the one we had in 2018, were not that rare back then.” click here

Tobias Scharnweber, Karl-Uwe Heußner, Marko Smiljanic, Ingo Heinrich, Marieke van der Maaten-Theunissen, Ernst van der Maaten, Thomas Struwe, Allan Buras & Martin Wilmking . Removing the no-analogue bias in modern accelerated tree growth leads to stronger medieval drought. Scientific Reports, volume 9, Article number: 2509 (2019).

In many parts of the world, especially in the temperate regions of Europe and North-America, accelerated tree growth rates have been observed over the last decades. This widespread phenomenon is presumably caused by a combination of factors like atmospheric fertilization or changes in forest structure and/or management. If not properly acknowledged in the calibration of tree-ring based climate reconstructions, considerable bias concerning amplitudes and trends of reconstructed climatic parameters might emerge or low frequency information is lost. Here we present a simple but effective, data-driven approach to remove the recent non-climatic growth increase in tree-ring data. Accounting for the no-analogue calibration problem, a new hydroclimatic reconstruction for northern-central Europe revealed considerably drier conditions during the medieval climate anomaly (MCA) compared with standard reconstruction methods and other existing reconstructions. This demonstrates the necessity to account for fertilization effects in modern tree-ring data from affected regions before calibrating reconstruction models, to avoid biased results.

Earth system models underestimate carbon fixation by plants

Alexander J. Winkler, Ranga B. Myneni, Georgii A. Alexandrov, Victor Brovkin. Earth system models underestimate carbon fixation by plants in the high latitudes. Nature Communications, 10, 885, 2019.

Most Earth system models agree that land will continue to store carbon due to the physiological effects of rising CO2 concentration and climatic changes favoring plant growth in temperature-limited regions. But they largely disagree on the amount of carbon uptake. The historical CO2 increase has resulted in enhanced photosynthetic carbon fixation (Gross Primary Production, GPP), as can be evidenced from atmospheric CO2 concentration and satellite leaf area index measurements. Here, we use leaf area sensitivity to ambient CO2 from the past 36 years of satellite measurements to obtain an Emergent Constraint (EC) estimate of GPP enhancement in the northern high latitudes at two-times the pre-industrial CO2concentration (3.4 ± 0.2 Pg C yr−1). We derive three independent comparable estimates from CO2 measurements and atmospheric inversions. Our EC estimate is 60% larger than the conventionally used multi-model average (44% higher at the global scale). This suggests that most models largely underestimate photosynthetic carbon fixation and therefore likely overestimate future atmospheric CO2 abundance and ensuing climate change, though not proportionately.

Climate science does not support media claims regarding “climate change”

“In the first 5½ months of 2019, over 200 scientific papers have been published that cast doubt on the position that anthropogenic CO2 emissions function as the climate’s fundamental control knob…or that otherwise serve to question the efficacy of climate models or the related “consensus” positions commonly endorsed by policymakers and mainstream media sources.” click here

A serious discussion of climate and changes in climate is needed, not snarky comments about “climate deniers”.

“Gavin Schmidt has posted a commentary on the video of a talk I gave recently at Purdue University. I’m grateful for his attention and comments, as I’m always trying to improve my presentations. It seems that I failed to get my points across in some crucial places, so I’ve got work to do.

As part of that work, I offer below some responses to Schmidt’s comments . I have reformatted his original text as block quotes and removed figures to improve the readability of this response. I’ve also, without changing meaning, removed some of his snark, which has no place in a serious discussion.

Steve Koonin, June 17, 2019″. click here

California heat lower than past extreme levels

“On June 17, 1859, Santa Barbara, California was so hot that no humans could be outside, and there was widespread destruction of animals and plants.  Fruit burned on one side and fell to the ground.” click here

“Climate change” is not endangering the planet, but climates change

“Climate change is not a hoax, but as a political matter, it is a persistent pretext for expanding government control over the economy, redistributing wealth, and empowering unaccountable elites at the expense of voters and their elected representatives. This pretext rests on three falsehoods:

  1. Science has determined that climate change is a “planetary emergency”—a rapidly unfolding global catastrophe.
  2. A panoply of market-rigging interventionist policies, called “climate solutions” by their proponents, can deliver meaningful climate protection at reasonable cost.
  3. Only deluded science deniers or greedy polluters oppose such policies.

In fact, climate change does not endanger the survival of civilization or the habitability of the planet. So-called climate solutions are bureaucratic power grabs and corporate welfare schemes with no detectable climate-related benefits. Opposition to such policies is prudent regardless of one’s views on climate science.” click here