Man made global warming, that’s a big no. There has been no global warming since 1998. The amount of warming prior to that was about as long as the plateau and cooling since then to the present. Leftist claim to have indisputable science, sure it is when you totally eliminate facts such as the Medieval Warming Period.
Prior to that there was a period of cooling so pronounced that some scientists in the 1970s were warning of another “ice age.” Prior to that was a period of warming that still holds the high temperature records in the United States for the past 5 or 6 centuries. Prior to that was a small period of cooling preceded by another slight warming period that started in the late 1800s. Before that was a slow warm-up from the mini-ice age that took place after the Medieval Warm Period (MWP), preceded by much colder temperatures that went all the way back to the Roman Warm Period (RWP) around the time of Christ’s birth. Before that was even a much colder period with fluctuating lows and highs until about 1200 or so BC and the Minoan Warm Period (MinoanWP). Prior to that there were millennia of cold warming up into the Holocene Warm Period (HWP) about 6000 BC.
Incidentally, if you chart the warmth of the HWP across the MinoanWP, the RWP, the MWP, to the little bit of warming in the 20th century, you’ll see a marked decline in maximum temperatures for each of these periods. It’s getting colder. And if you do the same for the preceding 4 inter-glacial periods and the one we’re in currently, you’ll see the same decline in maximum global warmth. And even scarier is that the intervening glacial periods track colder and colder as well. Oh, hey, did you know that Antarctic sea ice has increased by 53% since 2006? Doesn’t sound like warming.
In a BBC interview on 13 February 2010, Phil Jones agreed that from 1995 to 2009, the global warming “trend (0.12C per decade) is positive, but not significant at the 95% significance level”, though close. This has been misleadingly reported by some news sources. On 10 June 2011 Jones told the BBC that the trend over the period 1995 to 2010 had reached the 95% significance level traditionally used as a threshold by statisticians.
While HadCRU reported an extreme peak in global temperature in 1998, the GISS and NCDC estimates showed a lower peak in 1998, and more subsequent warming. The National Oceanic and Atmospheric Administration reported that the decade 2000-2009 was the warmest on record for the globe, with 2005 the warmest year.
During the Little Ice Age (roughly 1500 to 1850) CO2 concentration in the atmosphere reached dangerous lows. Most plants require at least 150 PPM to survive, it is their main food, we got down to 200 PPM or so. Optimum for plants is around 1100 PPM and we need plants to survive on the planet. Geologicaly speaking, the Earth’s atmosphere should have around 500 to 1000 PPM of CO2 to be optimal. The last few million years are unusual in that CO2 is so low. We are simply recovering to normal. Current CO2 concentrations are around 340 PPM and to call CO2 a pollutant is simply stupid, it is required for life on Earth, no less than Oxygen.