A Warm Period by Any Other Name – The Climatic Optimum

by Tim Ball, July 31, 2016 in WUWT


Hypsithermal, Altithermal, Holocene Optimum, Holocene Thermal Maximum, Holocene Megathermal, Anthropogene;

There is frustration and reward when an article appears on the same topic of an article you are completing – in this case the Holocene. Such was the case this week with Andy May’s article “A Review of temperature reconstructions.” Andy points out the basic problems of reconstruction using proxy data for the most recent half of the Holocene – an issue central to historical climate and climate change studies. His paper did not alter my paper except as it reinforces some arguments.

This article examines the entire Holocene and illustrates the history that influenced the studies. There are two distinct parts to the studies, the pre and post Intergovernmental Panel on Climate Change (IPCC). The former is a genuine scientific struggle with issues of terminology and reconstruction, and the latter a scientific struggle to impose a political perspective regardless of the evidence. Because of the damage done to climatology by the proponents of anthropogenic global warming (AGW), both parts require explanation.

Japan’s JMA Claim Of “Relatively Small” Urbanization Effect Likely An Understatement Of Multiple Degrees

by Kirye and P. Gosselin, August 17, 2018 in NoTricksZone/JapanMeteorologicalAgency


Aerial photos show that the 15 temperature observation stations the JMA is using to determine mean temperature anomalies are likely impacted far more by urbanization than the agency claims.

 

Abashiri is in the middle of buildings and streets.

Why does climate sensitivity increase over time in models? A look at two possibilities

by A. Zaragoza Comendador, August 16, 2018 in WUWT


Note: if the terms used in this article seem confusing, check out the previous one.

Introduction

It’s well known that climate models show increasing sensitivity over time: for a given forcing, the true long-term temperature increase (ECS) is higher than what you’d estimate if you simply extrapolated from the past (ECS_hist). In other words, the ECS-to-ECS_hist ratio is above 1. This article tries to work out why climate models behave like that; that is to say, the variable I’m trying to explain is the ECS-to-ECS_hist ratio.

Now, there’s probably too many hyphens and underscores in the text. So it will be more readable if I clarify that, every time I talk simply about ‘correlation’, I mean the correlation of thing X with the ECS-to-ECS_hist ratio. If other kind of correlation is mentioned, I’ll say so explicitly.