Since 1998 has the earth warmed?

Question

If not, why has it not? Are we on the shaft of an upside down hockey stick? Some scientists are saying we should be bracing ourselves for a significant cool down, and perhaps even increase Co2 production to counteract the cold's devastating effects on our plant life.

Answer 1

The regression slope for global temperature anomaly for the period 1998-2007 is +1.8° C per century. So yes, the world has warmed since 1998, although climatologists generally don't like to use statistics over timespans shorter than 30 years.

It should be noted that 1998 was, at the time, the warmest year ever recorded. Although it has since been surpassed by 2005 as the warmest year, it may be useful to note that global warming deniers always use 1998 as a "starting" year for such bogus claims, because it's a statistical outlier. For example, the regression slope for the period 1999-2007 is +3.1°C per century.

2007 was the second-warmest year on record globally. This makes fifteen years IN A ROW that we have experienced a top-ten warmest year, and 21 out of the last 22 years have been in the top-ten warmest at the time.

The last time we had a top-ten coldest year was 1917.

Answer 2

No the earth has not warmed in the last decade. This is a problem for all those who proclaim man as the great spoiler of the planet, since CO2 levels have increased. As for the hockey stick, please never say that name as the original was such a huge lie to the public. As for the fate of the planet, no one knows. We are at the mercy of the sun.

Answer 3

Sure.  Here's good data, confirmed by independent scientists.

http://data.giss.nasa.gov/gistemp/2007/

discussed in detail, with confirmation, at:

http://tamino.wordpress.com/2008/01/24/g...

Very few scientists believe we're in any danger of cooling.  And they have no good data to back them up.  Just a wild theory.

On the other hand, all these guys, backed by a mountain of data from all over the world, think we're in danger of a very damaging warming.

The National Academy of Sciences, the American Association for the Advancement of Science, the American Institute of Physics, the American Chemical Society, the American Geophysical Union, the American Meteorological Association, etc.  EVERY major scientific organization.

You wouldn't want to bet your future well being that they're wrong, and a few guys with nothing but wild theories right.  No sane world leader would.

Answer 4

The data is inconclusive.

Answer 5

i have no idea, but my totally unqualified feelings indicate the advance of another Ice Age. According to pilots i met in the sixties who flew to Antarctica, there never was an Ozone layer. They referred to it as 'a hole' which allowed UV and whatever in and this was born out by the colour of their faces, very dark mahogany.

Answer 6

By most measures, yes.  The rolling five year average (calculated from GISS land-ocean index data) increased by 0.178 degrees Celsius between 1998 and 2007.  This same average appears to have leveled off in the past three years, however.

Dana, the GISS data is not a five year running average, its a string of five year averages centered on the third year in each grouping.  The five year running average (which I calculate every year) shows a similar trend, but it is offset by two years.  It also shows and increase since 1998, but a leveling since 2005.  Linear best fit lines are essentially meaningless when the data has as much scatter as we see in annual average global temperatures.  The correct way to determine the trend is to average the annual rate of change.  If this average is positive, then the trend is upward.  If it is zero, then there is no change, and if it is negative, then the trend is downward.  Quantitative analysis is always better than graphs.  Numbers are always better than pretty pictures.

Keith P, same comment about regression lines.  They are meaningless when applied to data with as much scatter as global temperatures.

Answer 7

NO!! But the all the hype sure gives some companies a good excuse to get on the bandwagon and label their products "green" or "enviormentally friendly" and then charge more for them. I'm all about doing my part to make the most of the resourses I have, recycling, conserving water etc... But I do not like all the hype about the Global Warming when they have yet to prove it and the Earth has not warmed in over 10 years and the data they are using does not include all the weather stations that have closed in the last 10 years many of which are any extremly inherantly cold climates. I'm just tired of companies raping my pocketbook because I want to do the right thing and make sure my grandkids and their kids and kids kids have a wonderful world to live in.

"In a stunning turn of events data (quietly) released by NASA shows that the 4 warmest years ever recorded occurred in the 1930's, with the warmest year on record being 1934 (not 1998). Lets see if Al Gore revises his road show." "NASA Revises Temperature Data - 1930's warmest on record!"

Answer 8

It hasn't warmed since 1998 despite CO2 increasing at unprecedented rates.  The rapid warming which occured early last century indicates that there are other things besides CO2 which can cause the Earth to warm.

The physical properties of CO2 just don't justify the theory that CO2 has caused a measurable amount of warming.  The frequency band that CO2 absorbes is so narrow and the effect is already saturated.  There is no point trying to warm the Earth with CO2 emissions - it won't work.

Answer 9

Yes, it has.  Five year running average:

http://data.giss.nasa.gov/gistemp/graphs...

Best fit line since 1998:

http://tamino.files.wordpress.com/2007/0...

Frew if any scientists believe the planet is going to cool down.  Some solar scientists have said that the next solar cycle (in approximately 11 years) will be a weak one.  However, when they say there will be cooling, they simply mean that the forcing from solar output will decrease.  They are not taking other forcings into account, such as human CO2 emissions.  

Additionally, this will be one weak 11-year solar cycle.  It's a short-term effect, and one which will almost certainly be overwhelmed by increasing CO2 anyway.