The Earth's albedo (or reflectance) is the fraction of shortwave solar radiation that it reflects back to space. It is an essential determinant of the earth's climate, since, in the broadest sense, changes in climate arise from the simultaneous evolution of the solar intensity, the Earth's albedo, and greenhouse insulation.In the mid-1990's, the changing albedo was (and probably still is) the least understood of the three parameters (Houghton, 2000;IPCC, 2013). That uncertainty motivated our effort to measure of the earth's albedo continuously throughout at least one full solar cycle (two decades). The long data series would also help explore any correlations that might exist between varying solar activity and terrestrial reflectance (Gray et al.

The New Solar Telescope (NST) project at Big Bear Solar Observatory (BBSO) now has all major contracts for design and fabrication in place and construction of components is well underway. NST is a collaboration between BBSO, the Korean Astronomical Observatory (KAO) and Institute for Astronomy (IfA) at the University of Hawaii. The project will install a 1.6-meter, off-axis telescope at BBSO, replacing a number of older solar telescopes. The NST will be located in a recently refurbished dome on the BBSO causeway, which projects 300 meters into the Big Bear Lake. Recent site surveys have confirmed that BBSO is one of the premier solar observing sites in the world. NST will be uniquely equipped to take advantage of the long periods of excellent seeing common at the lake site. An up-to-date progress report will be presented including an overview of the project and details on the current state of the design. The report provides a detailed description of the optical design, the thermal control of the new dome, the optical support structure, the telescope control systems, active and adaptive optics systems, and the post-focus instrumentation for high-resolution spectro-polarimetry.

The overall reflectance of sunlight from Earth is a fundamental parameter for climate studies. We have designed and implemented small aperture, remote control telescopes in Big Bear Solar Observatory in California and in Tenerife in the Canary Islands. These telescopes observe the earthshine to obtain a global mean terrestrial reflectance utilizing a coronagraph-like design for long exposures of the dark of the Moon and have internal moving parts in the optical train, which presented some design and control problems.