Sunday, October 19, 2014

Climate Change: The Global Scenario

I learned that all of the events of the past decade, all of our memories have something in common. They all took place during the hottest decade ever recorded since humans begin keeping temperature records about 150 years ago.
In the last decade, the earth's temperature raised roughly a third of the degree Fahrenheit since 1880. It's risen about 1 1/2 degrees. You might say the Earth's having a fever and science has predicted that it's going to be much worse.
The global sea level rose by over an inch during the decade, almost twice as fast as the average during the 20th century. Arctic summer sea ice is declined by over 300,000 sq. miles, enough ice to cover the States of Texas and Kentucky.
Majority of climate scientists say evidence are human-caused warming quicker but less understood is exactly how this warming could change the complex interactions between our planet's land, water, sky and the different organisms we have in our world.
As NASA scientists improve their understanding and predictions about climate change, NASA satellites provide critical data about what's happening on our planet today, real life observations scientists use to hone their predictions. And NASA gets a global view of the three major pieces of the climate puzzle:
1            1) How much of the sun's energy is heating the earth
              2) How much of that energy is being reflected back to the space
              3) How much is being trapped, heating the planet.
NASA satellites measure the sun's energy which fluctuates 2 to 10 years of cycle. Could increase in solar activity cause global warming? Satellite evidence shows us that solar cycle has only a slight impact on our planet's temperature.
The second piece of our temperature puzzle is our planet's brightness? All other things being equal, a brighter or reflective planet bounces more energy back to space. Some of the brightest or the most reflective are those covered with ice.  NASA imagery shows those area shrink, especially in the Arctic. As sea ice manages into darker oceans, our planet becomes less reflective and warms even further. Clouds also reflect amount of sunlight. As our planet warms, more water evaporates, creating more clouds. More cloud covering increases the planet's brightness, helping to cool the planet. But clouds and the small particles called the aerosols that help perform our climate wild cards. Many current climate models predict some cooling could increase cloud cover. But will it be enough to significantly slow warming? Scientists are using NASA data for the answer.
Further complicating issue is that water vapor is actually the world's most abundant greenhouse gas, the same molecules that might cool the planet in cloud for actually warm even in the form of gas.

Carbon dioxide is the second most abundant greenhouse gas, and our biggest contribution to global warming. Fossil fuels burning releases large amounts of carbon dioxide into the air. NASA satellites capture the infra-red signature of carbon dioxide in the global atmosphere. NASA also monitors other greenhouse gases like methane, nitrous oxide, and CFCs.
Greenhouse gas is most likely the main contributor to current global warming. It's the key piece to the temperature puzzle, to unlock the door in higher and higher temperatures.
2010, marks the hottest decade ever recorded so far. What will the next 10 years become for our planet? Computer models predict even warmer temperature, extreme weather, less ice, and higher seas.
"The severity of those changes will depend partly on how our planet's complex system responds and more importantly, on what choices we make."

                I watched a video and powerpoint presentation about “Climate Change: The Global Scenario.”

                I participated in the online discussion by expressing thoughts and ideas about this topic in my blog and by sharing what I learned on the video presentation that I watched.


Post a Comment