An unbiased economic score card shows Global Warming has increased the GDP by 1.3% so far

How Much have Global Problems Cost the World? A Scorecard from 1900 to 2050 was editted by Bjørn Lomborg with many contributors They use an unbiased or at least a consistent methodology to assess the impact of global problems from 1900 to today and project forward to 2050.

There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts.

It will come as a big surprise that climate change from 1900 to 2025 has mostly been a net benefit, rising to increase welfare about 1.5% of GDP per year. Why? Because global warming has mixed effects and for moderate warming, the benefits prevail. The increased level of CO₂ has boosted agriculture because it works as a fertilizer and makes up the biggest positive impact at 0.8% of GDP. Likewise, moderate warming avoids more cold deaths than it incurs extra heat deaths. It also reduces the demand for heating more than increases the costs of cooling, totaling about 0.4%. On the other hand, warming increases water stress at about 0.2% and negatively impact ecosystems like wetlands at about 0.1%. Storm impacts are very small, as the total storm damages (including naturally caused storms) are about 0.2%.

Accidental truth telling from the left. Warming is good for humans. But its still our fault.

First there is Historical Global Warming. We can see that from temperatures. It is pretty factual, though small. The major uncertainty is from the fact that a lot of official weather stations were located at airports for convenience, and cities have grown up around them, so the weather stations are now located in a more severe heat island than they were in the 1900s. Heat islands cool the surrounding area, so measuring only the hot part is biased, but we can censor out the corrupted sensor locations.

Then there is Anthropogenic Global Warming.
That is a guess at what causes HGW. The fact is some may be caused by us, some by volcanos, some by CO2 from the water escaping. The fraction is unknown. People that pretend to know are frauds.

Then there is Future Global Warming. We don’t know how to quantify that, can’t because of the nonlinearities inherent in the system. People who pretend to know are frauds.

Then there is Anthropogenic Future Global Warming. We don’t know how various causes of AFGW will interact, because of nonlinearities we are uncertain of the future quantities, and the degree of interaction depends non-linearly on the quantity. People sho pretend to know are frauds.

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.