Evidence of global warming is being meticulously accumulated by climate change experts and allied scientists all over the world. Convincing evidence has proved that certain gasses have the tendency to trap heat, making them act as a blanket that prevents longwave (terrestrial) radiation reflected by the earth’s surface from escaping into space – creating what is referred to as the greenhouse effect. The two most significant of the greenhouse gasses (GHGs) are carbon dioxide (CO2) and ozone (O3). CO2 is released into the atmosphere through the burning of fossil fuels – coal, oil, and natural gas – used to power vehicles, heat homes and generate electricity. The need for these fossil fuels keeps growing each day resulting in overload of GHGs in the atmosphere. As a result, more and more heat is trapped by this invisible blanket and the earth keeps warming up. How do we know? Below are the top 10 scientific facts and evidence of global warming in 2015. Read on!
1. Melting Ice
Evidence from satellite imagery indicates a steadily accelerating loss of Antarctic ice. Surprisingly, new pieces of evidence points to the fact that even the East Antarctica, previously thought to be too stable to lose ice mass, has begun losing its content. Greenland ice has also been found to be a steady loss. The Arctic sea-ice loss is even accelerating much faster with the loss rate estimated to exceed models forecasts by factor said to be approximately 3. River ice and lake ice, covering throughout Northern Hemisphere have been found to freeze much later, but break up very early.
2. Shrinking Of Glacier Volume
Global glaciers are shrinking at a more accelerating rate than expected. This has been one of the most pronounced effects of climate change. Glaciers cover about 10 percent of the global land and are the world’s largest reservoir of fresh water –holding approximately 75 percent. The retreating glacier is caused by warmer temperatures that are causing increased evaporation due to the wind and warmer weather. Glaciers often respond very quickly to changes in climate.
3. Rise In Seal Levels
With the melting of ice over land and seas, sea level variations have been observed. According to the Intergovernmental Panel on Climate Change (IPCC’s) 2007 report, ice loss to the seas are the most important cryospheric contributor to the sea and is currently responsible for almost all the sea level rise estimated to be an average of 0.77 ± 0.22 mm annually. Recent scientific studies show that the movement of ice streams towards the seas has increased significantly, with some doubling in just a few years resulting in more and more water emptying into the oceans.
4. Global Rise In Surface Temperature
Temperature readings from across the globe show that global warming is real. Based on scientifically collected data over the past 130 years, average global temperature has been on the rise with a value of 1.50F per year. With increasing emission of CO2, heat that would escape freely into space is trapped in the lower layers of the atmosphere, thus warming the earth. This warming is accelerating. In fact, satellite data confirm that much less heat is escaping our atmosphere today than 30 years ago.
5. Extreme Weather Events
Extreme weather and climatic events, most notably, floods and drought, are becoming more frequent and catastrophic. The Climate Extreme Index (CEI) values from all regions of the world have emerged as the most objective way of determining whether these extreme events are rising. The results have been mesmerizing. Additionally, we often here every day about these weather extremes such as tornadoes, floods, droughts, tsunamis among others killing hundreds to thousands of people and destroying properties throughout the world.
6. Decreasing Snow Cover
In recent decades, the global annual snow cover has been on the decline. This pattern has been consistent with increasing global temperatures. The Northern Hemisphere snow cover is said to be no longer enough to Santa’s home. Based on National Ice & Snow Data Center findings, the amount of Northern Hemisphere’s snow cover was at a record low. The 2011 amount was about 3 million square miles below the 1979’s average and 860,000 square miles below the 2000’s average.
7. The sun Isn’t Getting Any Hotter
The sun often seems brighter and hotter for most of us, however, this is simply pure perception rather than an indication of the increase of luminosity and heat of this biggest star. According to NOAA, the sun has always maintained its normal and natural 11-year cycle (sunspot cycle) characterized by small energy fluctuations, but with no net temperature increase between 1980 to 2010. During this same period, there had been a great increase in global temperature. This fact thus nullifies the myth that the sun could be contributing to the rapid global warming.
8. Rising Upper Ocean Heat Content
The content of heat within oceans varies significantly from one place to another and from year to year. This variation is mainly due to natural variability and, most important, changing ocean currents. Observed measurements indicate a steadily rising heat content in the oceans which scientists say is consistent with the rise in sea level. The sea level rise is mainly caused by thermal expansion of the ocean water as it warms.
9. Evidence From Archived Data
The climatological and weather records based on direct measurements of temperature using thermometers and satellite instruments dates back to only 150 years. So to help us gain more in-depth knowledge about global warming and climate change, proxy data is used for measurements of climatological variables from as back as 800,000 years. The most commonly used proxy data include the core of the sea floor made by IODP (Integrated Ocean Drilling Program), ice cores derived from thick ice sheets in Greenland, Antarctica, Dendrochronology and analysis of pollen.
10. Shifting Ecosystem
There has been constant loss of species adapted to melt water stream conditions. Animals and plants that strongly depend on the hydrologic impacts of glacial ecosystems are poised to suffer significantly as water temperature; river channel stability and suspended load are continuously altered. The distribution of plants, mammals, birds, reptiles, find and marine invertebrates is shifting towards the poles. Additionally, growing season is lengthening, and there has been a drop in primary productivity due to unprecedented warming. UK flowers are now blooming much earlier than they were 200 years ago, species are shrinking and Melbourne butterflies are beginning to emerge earlier than expected.