Have we reached the point of no return on the road to runaway warming ending in near-term global mass extinction (including humans)?

Some call me a 'climate scientist'. I'm not. What I am is an 'Earth systems generalist'. Born in 1939, I grew up with passionate interests in both science and engineering. I learned to read from my father's university textbooks in geology and paleontology, and dreamed of building nuclear powered starships. Living on a yacht in Southern California I grew up surrounded by (and often immersed in) marine and estuarine ecosystems while my father worked in the aerospace engineering industry. After studying university physics for three years, dyslexia with numbers convinced me to change my focus to biology. I completed university as an evolutionary biologist (PhD Harvard, 1973). My principal research project involved understanding how species' genetic systems regulated the evolution and speciation of North America's largest and most widespread lizard genus. Then for several years as an academic biologist I taught a range of university subjects as diverse as systematics, biogeography, cytogenetics, comparative anatomy and marine biology. In Australia, from 1980, I was involved in various activities around the emerging and rapidly evolving microcomputing technologies culminating in 2 years involvement in the computerization of the emerging Bank of Melbourne. In 1990 I joined a startup engineering company that had just won the contract to build a new generation of 10 frigates for Australia and New Zealand. In 2007 I retired from the head office of Tenix Defence, then Australia's largest defence engineering contractor, after a 17½ year career as a documentation and knowledge management systems analyst and designer. At Tenix I reported to the R&D manager under the GM Engineering, and worked closely with support and systems engineers on the ANZAC Ship Project to solve documentation and engineering change management issues that risked the project 100s of millions of dollars in cost and years of schedule overruns. All 10 ships had been delivered on time, on budget to happy customers against the fixed-price and fixed schedule contract. Before, during, and after these two main gigs I also did a lot of other things that contribute to my general understanding of complex dynamical systems involving multiple components with non-linear and sometimes chaotically interacting components; e.g., 'Earth systems'. Earth's Climate System is the global heat engine driven by the transport and conversions of energy between the incoming solar radiation striking the planet, and the infrared radiation of heat away from the planet to the cold dark universe. As Climate Sentinel News Editor, my task is to identify and understand quirks and problems in the operation of this complex heat engine that threaten human existence, and explain to our readers how they can help to solve some of the critical issues that are threatening their own existence.