Presentation is loading. Please wait.

Presentation is loading. Please wait.

PLANET EARTH: FRAGILE AND EVER-CHANGING Ashok Sahni INSA

Similar presentations


Presentation on theme: "PLANET EARTH: FRAGILE AND EVER-CHANGING Ashok Sahni INSA"— Presentation transcript:

1 PLANET EARTH: FRAGILE AND EVER-CHANGING Ashok Sahni INSA Senior Scientist Earth is yrs old; Life yrs, Industrialization 300 yrs

2 Thermal Regime for a Living Planet
VENUS Thermal Regime for a Living Planet 121C to-167C Int. Space Stn. MARS

3 Fate of Earth?

4 Present Day Species Diversity

5 Greenhouse earth Greenhouse earth Icehouse earth-present Snowball Earth Cryogenian ca. 650 ma Icehouse earth 250 ma+

6

7 Disasters: Common, happening or yet to happen!
FREQUENCIES: ANNUAL TO KILO YEARS-SURFACE AND INTERNAL (PLANETARY) STRESSES:- droughts, floods, landslides, earthquakes/tsunamis, volcanic eruptions (within record of human civilization) FREQUENCIES: KILO YEARS OR MORE-SOLAR OR COSMIC FORCING:- Climate Change-Solar radiations and water budget CO2/O2 /O3 enhancement and depletion. Cometary Impacts: ( note Tunguska 1908, Lonar, India (10kyr), Shoemaker –Levy on Jupiter 1994. Anoxia-relatively sudden decrease in atmospheric O2 Ecosystem collapse-corals, tropical rainforests, large mammal niche etc

8 Global Mean Annual Temperature Distributions at 0 & 100 my

9 Long term climate change perspective ( myrs)

10

11

12

13

14 Sun unusually active during last 50 years
Monthly Sunspot no

15 Sea level rise

16

17 Atmospheric O2 & C02 and evolution of life ( greening of the earth)
20.9%PAL O2 CO2 6-8% PAL

18 Cyclic Solar Energy input drives Earth’s Climate and Weather
Cyclic Solar Energy input drives Earth’s Climate and Weather. Greenhouse Gases . Phyto (nanno)plankton are a powerful Biologic Pump to drastically reduce Greenhouse Gas CO2 Emiliania huxleyi NASA’s Sea-viewing Wide Field-of-view Sensor (SeaWiFS) can accurately measure Climate Change reflected by Phytoplankton

19 Climate change: ocean current gyre

20 Primrose: Decoration for man: landing pad for an insect!!
Adjusted for UV light as seen by insects Dawkins: Greatest Show on Earth: 2009

21 ICEBERGS WILL MELT! BUT…
IF YOU WANT TO LIVE IN HARMONY WITH THE EARTH, TRY TO UNDERSTAND IT NO NEED TO PANIC!!


Download ppt "PLANET EARTH: FRAGILE AND EVER-CHANGING Ashok Sahni INSA"

Similar presentations


Ads by Google