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Explore the various perspectives and debates surrounding global warming, including the IPCC perspective, the "Hockey Stick" graph controversy, and the role of oceanic circulations, solar intensity, and cosmic rays in climate change.
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No Consensus • Roger Pielke Sr.’s poll • 1. The largest group of respondents (45-50%) concur with the IPCC perspective as given in the 2007 Report. • 2. A significant minority (15-20%), however, conclude that the IPCC understated the seriousness of the threat from human additions of CO2. • 3. A significant minority (15-20%), in contrast, conclude that the IPCC overstated the role of human additions of CO2 relative to other climate forcings.
Is Modern Warming Unprecedented? • I’d say no. • In 1998, Michael Mann, Ph.D. released this graph to the scientific community.
Ross McKitrick, Ph.D. and Steve McIntyre began a project to deconstruct the “Hockey Stick” graph on the basis that it is not statistically sound. • The Hockey Stick graph uses tree rings as a proxy for temperature. • Using PC analysis, Mann essentially “mined” for a hockeystick trend. • More weight was given to Bristlecone Pine and Foxtail trees because they showed more variance.
The Censored Directory Backto_1400-CENSORED showed that Mann had calculated the trend without Bristlecone Pines to test its robustness.
Loehle 2007 No tree-ring data. All data was peer-reviewed and calibrated for local temperature. First paleoclimate reconstruction to issue a correction. Loehle shows a strong, GLOBAL Medieval Warm Period/Little Ice Age.
Now here’s what I think about Global Warming. • After much research, my conclusion is that ocean current variability, changes in solar intensity, and a mechanism that links the two are the causes of climate change over the long term and recently.
Here’s the same graph of global temperatures. • Now, you can see a warming trend, cooling trend, and another warming trend. Find the exact date of the beginning of the first warming period, the beginning of the cooling period, and the beginning of the second warming period. The dates 1913, 1942, and 1978 are named by Tsonis et al. to be dates of oceanic synchronization and shifts in climate.
Tsonis et al. • A new dynamical mechanism for major climate shifts. • Consistent with the theory of synchronized chaos. • There are four main oceanic circulations: • The Pacific Decadal Oscillation (PDO) • The North Atlantic Oscillation (NAO) • El Nino/Southern Oscillation (ENSO) • North Pacific Oscillation (NPO) • Occasionally, these oscillations synchronize. In other words, occasionally, these all hit their highest or lowest intensities at the same time. • This, Tsonis argues causes climate changes by changing El Nino frequency.
The Great Climate Shift • In the late 1970s, the climate took a significant shift, not just in temperature, but in precipitation and wind trends. • Central Pacific cooled. • Ocean off of the Western Coast of North America warmed. • Climate in the Northern Hemisphere was altered. • This shift triggered a change in El Nino variability. • More El Nino=higher global temperatures • More La Nina=lower global temperatures • Since the Great Climate Shift, we’ve seen an increase in El Nino strength and occurance.
The Solar Explanation Our Sun is a variable star, which means its brightness varies. Ours varies in several cycles, including an 11 and 22 year cycle.
Long term changes in TSI • Solar irradiance varies over the long term too.
Total Solar Irradiance May Be at Levels Higher Than Any for 8,000 years. • Since 1600, solar irradiance has increased, and so have temperatures.
The Problem with the Solar Theory • Yet, solar irradiance may not have increased since the 1980s, while temperatures have continued to climb. • Why? • I would argue that temperatures have truly leveled out during this decade, which means warming from 1980 to 2000 is unaccounted for. • This, for me, is the main flaw in the theory. Although, I do believe the Sun is a driver of climate over the long term.
Could Supernovae be Changing Our Climate??? • Cosmic rays are small, energized particles that fly around in space, emitted from imploding stars in the belt of the Milky Way that Earth inhabits. • As they fly towards the Earth, solar winds block some from entering the Earth’s atmosphere. • Once the cosmic rays enter the atmosphere they bombard particles in the upper atmosphere, creating a shower of smaller particles, that then ionize low altitude water vapor, creating clouds that cool the Earth. • When solar intensity changes, the intensity of solar winds change too, causing changes in the amount of cosmic rays entering the Earth’s atmosphere, changing the amount of cloud cover. • Essentially, the Sun regulates terrestrial low cloud cover.
But Solar Winds do not follow TSI exactly! • While TSI has remained the same since the 80’s, solar wind intensity increased through the 90’s. We measure solar wind intensity through Interplanetary Magnetic Field strength.
Now Here’s the Theory that Connects It all! • Tim Patterson, Ph.D. was being employed by a fishing company to attempt to find trends in fish populations, because they were having a bad year. • By the end of his research, he concluded that solar cycles were influencing atmospheric and oceanic circulation.
Aleutian Low and North Pacific High The Aleutian Low’s position is influenced by the position of the polar jet stream. Likewise, the N. Pacific High’s position is influenced by the position of the subtropical jet stream. The region being studied by Patterson happens to be right between the two circulations, so by looking at what circulation is dominant when, we can deduce the position of the jet streams.
Looking at the Sediments In the sediments, he found several solar cycles, including: • ~11 yrSchwabeCycle • ~75-90 yrGleissbergCycle • ~200-500 yrSuessCycle • ~1100-1500 yrBondCycle Shorter Time Longer Time
But how? • The Sun’s brightness is described as Total Solar Irradiance. This irradiance is made up of many different types, including X radiation, UV radiation, etc. • UV radiation alters the chemistry of the Ozone layer, affecting zonal circulation and planetary waves. • Planetary waves like the jet stream are pushed around in the atmosphere, altering their paths and intensities. • These changes in the jet streams alter oceanic circulation as evidenced by the changing domination of the Aleutian Low and North Pacific High.
And of course, I can’t forget to mention… • Changes in aerosol content from volcanoes and pollution. • Changes in the Earth’s wobble. • Changes in greenhouse gas content. • Changes in albedo due to glaciers. • Changes in land use & forest. • Changes due to urbanization. • Changes due to soot pollution. • And MORE The big picture is… Climate is complex! So many factors influence the climate that we do not yet understand. It seems ridiculous to me that we have determined that climate is influenced by only one factor – CO2. With our main source of heat changing in intensity and with giant oceans of heat moving and changing within the system, it seems odd that we ignore natural forcings.
So what about Carbon Dioxide? • Rising CO2 levels are not having a large effect on climate. • A strong CO2 forcing would cause five main terrestrial trends: • 1. Surface warming • 2. Arctic warming • 3. Antarctic warming • 4. Large Tropical Tropospheric warming • 5. Lower Stratospheric Cooling
Surface Warming • Yep, it’s happened, and you’ve seen the graphs. But, this powerpoint has been dedicated to showing you that the increased surface warming may be natural.
Arctic Warming • Yes, it is happening. But it has happened before and with the same magnitude, before CO2 was increasing rapidly. • Arctic temperatures follow perfectly with solar intensity.
Antarctic Warming • It simply hasn’t happened.
Tropical Tropospheric Warming • This is projected to be warming at three times the rate of the surface.
Lower Stratospheric Cooling • The trend did occur for about a decade, during which time the Ozone Layer was thinning, which would be expected to cause lower stratospheric cooling. Since then, there has been no trend.
