Increases in Global Temperatures:

Over the last 40 years in particular, there has been a significant rise in global temperatures.
2014 was the warmest year on record for both land and ocean temperatures since records began in the 19th Century.
The graph below shows the global average temperatures since 1880.

Retreating Glaciers:

The world's glaciers are beginning to retreat.
Up to 90% of the glaciers in Antarctica are facing destruction in the coming years.
The melting of the glaciers at the poles will cause a shift in current ocean currents, which will affect global temperatures.
It is believed that the melting of Northern glaciers will cause the gulf stream to migrate south. This could cause dramatic cooling in the UK.

Rising Sea Levels:

The global mean sea level has risen by 10-20cm in the past 100 years.
It is estimated that this adds up to 3mm per year since the 1990's.
Predicting this change into the future is difficult and it is unknown how much of an impact this process will have.
If sea level were to rise by 1 meter, many major cities such as New York would be underwater.
The melting of the Greenland ice sheet would cause sea level to rise by up to 7 meters, which would cause cities like London to be lost also.
This could lead to huge devastation worldwide.

Increasing Atmospheric Water Vapour:

Water vapor is known to be Earth’s most abundant greenhouse gas, but the extent of its contribution to global warming has been debated.
Atmospheric humidity increases with temperature.
However, the addition of water vapour to the atmosphere, for the most part, cannot be directly attributed to human generated activities.