Winter Landscape with a Bird Trap
Do you have global cooling a graph of the average temperature per year over the past 2000 years? I am trying to get a handle on this issue for myself.
First, I am a sceptic. I like to understand unbiased data.
1) Of course we are warmer than 500 years ago, that was during the Little Ice Age that ended during our Civil War. In 1789 the Hudson River froze and people could walk on the ice from Manhattan to Staten Island. Do we want to go back to those cold temperatures.
2) On the wikipedia graph it shows 2004 average temperature 0.75 degrees warmer than the average temperatures in 2004 of the 8 sources. This is a big difference. How can this be? They should be the same.
3) The Little Ice Age appears to have only affected the Western Hemisphere. Since these are global average temperatures, it must have been much colder in the Western Hemisphere during this time. Is this global cooling right?
4) According to the graph (not 2004 average temp) it appears that we are about at the same temperature as 2000 years ago.
5) Have you looked at CO2 concentrations during the different Ice Ages compared to now?
6) It appears that the major greenhouse gas is water vapor, not CO2. Is this true? Do you have information on their relative responsibility for warming?
Thank you again for your time and attention.
PS I remember clearly when all the environmental scientists stated that we were entering a global winter. The current hysteria appears to be manufactured with no scepticism as is necessary in a science.Barry's Response
- My one web page, about ancient climates,
has two graphs of the temperatures over the last 500 million years, but does not focus on the last 2000.
Philip refers to these on wikipedia.
The second one, titled reconstructed temperatures, shows the time period you're looking for. It looks like a composite of several scientific guesses that all say the same thing basically. We warmer now than anytime over the last 2000 and certainly warmer than 500 years ago after a previous period of global cooling.
Here's a closer look at these items:1. It's much warmer now
than it was 500 years ago during the Little Ice Age. People could walk from Manhattan to Staten Island on the Hudson River during this time. That won't happen today!
Human activities like releasing greenhouse gases into the atmosphere are supposedly causing the Earth's climate to warm. In contrast, the Little Ice Age only caused slightly cooler temperatures in some parts of the world. Floods, storms, and droughts were extreme weather events during the Little Ice Age. It wasn't a stable climate back then, so we don't want to go back. We can fight climate change by using cleaner energy sources and reducing greenhouse gas emissions. For us and for future generations, and this can make the world a safer and healthier place.
2. In 2004, the average temperature was higher than expected. Other sources predicted it would be .75 degrees hotter. It's a big difference, and it's not clear why.
Temperature measures the average kinetic energy of molecules in a system and is usually measured in degrees Fahrenheit, Celsius, or Kelvin. A temperature is a measure of how much energy molecules have in an area. Temperature is usually measured in Fahrenheit, Celsius, or Kelvin. Temperature readings can be affected by different instruments and methods.
Location and time of day can also affect the temperature. Average temperatures can be measured using climate data. Different sources of climate data may produce different results because they use different methods for calculating average temperatures or use different data. For a better understanding of the climate, it's important to look at it over a long period of time. To figure out what's natural and what's caused by humans, scientists study temperature data going back hundreds of years. Thousands of years of proxy data were presented by Al Gore in An Inconvenient Truth.
3. There was a period of colder temperatures between the 1300s and 1800s called the Little Ice Age. Scientists don't know if it affected the Eastern Hemisphere as much as the Western. During this time, it seems like the Western Hemisphere was colder.
Between the 16th and 19th centuries, there was a Little Ice Age. North America, Europe, Asia, and Africa were affected. Changing climates weren't the same everywhere, but it was a time of change. There's been a lot of change in the climate lately. Some parts of the world had cooler temperatures during the Little Ice Age. Human activities like burning fossil fuels are linked to rising temperatures. Droughts, floods, and storms are getting worse.
4. According to the graph, the average temperature today is the same as 2000 years ago.
Using proxy data, scientists estimate the global average temperature has risen by 1.8°F since pre-industrial times. It's a dramatic change, and it's largely caused by greenhouse gas emissions. Climate has always changed naturally over time, but now humans are messing with it too. It seems that as a result, temperatures are rising faster than ever.
5. Have we looked at CO2 concentrations during the Ice Ages?
During ice ages, CO2 levels were around 200 parts per million, and during interglacials, like the one we're in right now, CO2 levels have been around 280 parts per million. CO2 levels increase as global temperatures rise, scientists say. CO2 levels in the atmosphere were lower during ice ages because plants and oceans absorbed more of it. Plants grew slower because it's colder. Currently, we're in an interglacial period, when temperatures are warmer. CO2 levels in the air are higher than they've been for 800,000 years. The Earth is getting warmer along with this.
6. More than CO2, water vapor contributes to global warming. Together, they trap heat in the Earth's atmosphere, making it warmer.
Warmer temperatures increase the amount of water vapor in the atmosphere, amplifying these impacts. If global warming is caused by greenhouse gases in the atmosphere, methane and nitrous oxide are also important gases, but carbon dioxide is still the most important. By putting more carbon dioxide and other gases in the air, humans are helping to make the Earth warmer. Methane is more powerful at trapping heat than carbon dioxide, but there's less of it. Like you said, another important greenhouse gas is water vapor, but nobody knows for sure how great its impact is on climate change.
Bonus: In the past, many environmental scientists said we were entering a global winter. As a science, we need skepticism to understand the current hysteria.
Climate change is real and many things have caused the Earth to get warmer. Climate change is backed up by thousands of studies and the Intergovernmental Panel on Climate Change (IPCC). We learn about the world around us by observing and asking questions. In order to figure out how things work, they look at evidence. And found what they're looking for.
Search this site for more information now.